CURRICULUM VITAE

 

Massimo ROBBERTO

 

 

Date of Birth                 June 27th, 1958

Nationality                    Italian  

Address                        Space Telescope Science Institute (STScI)

3700 San Martin Drive

            Baltimore MD 21218, United States       

Phone                           +1 (410) 338-4382

Fax                               +1 (410) 338-4796        

E-mail                           robberto@stsci.edu

Web-page                     http://www.stsci.edu/~mrobberto

Languages                     English, French, German, Italian (mother tongue)

 

 

Education                      PhD in Physics                                                                                      1989

                                    Thesis: Astronomical Imaging in the Thermal Infrared:

                                                the TIRCAM project

Advisors: Prof. G. Silvestro and A. Ferrari, Università di Torino, Italy

 

Laurea in Physics (cum laude)                                                                 1984

Thesis: Millimetric and Infrared emission of the   Giant Molecular

            Cloud NGC6334

Advisor: Prof. G. Silvestro, Università di Torino, Italy

 

 

Positions:                      1999-date          Associate Astronomer

European Space Agency (ESA), on duty at the Space Telescope Science Institute 

1995-1999        Staff Astronomer

Max Planck Institute für Astronomie (MPIA), Heidelberg

                                    1995-1999        Research Astronomer [on leave]

Osservatorio Astronomico di Torino (OATo)

1987-1995        Research Astronomer, OATo

 

 

Current function            WFC3 Instrument Scientist (STScI)

                        WFC3 Infrared Group Lead (STScI)

WFC3 Infrared Detector Scientist (NASA)

 

Areas of Interest

Scientific:          Star formation in the Trapezium cluster; mid-IR emission of circumstellar disks; HST/UV studies of mass accretion in Pre-Main-Sequence objects; new mission concept.

Technical:         Design, construction, and commissioning of ground and space-based instrumentation; development and testing of new detectors; ground and on-orbit calibration strategies for HST instrumentation; JWST; LBT and VLTI/MIDI interferometers. Project management.

 

 

SYNOPSIS

 

Since I always wanted to be an astronomer, I was highly motivated when in 1986 I was admitted to the graduate school in Physics, the first graduate student ever in Astrophysics at my alma mater, the University of Torino. For my PhD thesis93 (1986-1989) I pioneered TIRCAM7,35, one of the first 10μm cameras built outside the US, based on a 10×64 Si:Ga detector. I did the feasibility study, contributed to the control SW and readout electronics, and participated to the commissioning runs at the 1.5m TIRGO telescope. In the meantime, in 1987, I won the national competition for a Research  Astronomer position at the Torino Astronomical Observatory. To foster my scientific research I became involved in a number of science projects mostly based on data I took at La Silla1,5,44,52,54, obtained with the IRAS satellite2,53, or both3,47,49. My range of interests extended to the theoretical studies of physical processes in the circumstellar medium42,43,45,48,51, polarimetry and CCD imaging55,56, and even on new methods to estimate the cosmic distance ladder with the SN1987A event46.

 

In 1989 I established the new technology group of the Torino Observatory, building from scratch an optical and cryogenic laboratory and contributing to the hiring process. With a small, highly motivated team I started in 1990 to devote most of my time to the development of new infrared instrumentation, in particular the ambitious TC-MIRC (Two Channels - Mid InfraRed Camera), for the TIRGO telescope26,28,36. TC-MIRC was the first instrument to cover with a single imager the entire 1-14μm wavelength range using an InSb device for the 1-5μm channel and a Si:Ga device for the 8-14μm channel. Both channels were simultaneously observing the same field, each with two independent, user-selectable, magnifications. The 10K cryogenic system has been the first entirely based on a closed-cycle-cooler for low-cost operations and easy maintenance at the remote site. As instrument PI, I developed the concept and the optical design, I negotiated the detector acquisition and export licenses, I followed the cryo-mechanical construction in Tucson, and wrote the graphic-user-interface and data analysis SW. First light occurred in 1994, then the instrument was offered to the public and has produced science data published on referred journals. TC-MIRC has given me a unique technical and managerial experience. Unfortunately, severe budget restrictions and staff departures delayed the construction.  When other teams developed new instruments based on IR detectors more advanced that our early, and noisy, 58×62 detectors, and developed them at 5 m class telescopes, the TC-MIRC/TIRGO combination became obsolete. It is therefore not surprising that after this experience my next mid-IR camera, MAX, was built at MPIA, but with a schedule that went from the concept to the deployment at the UKIRT telescope in only 9 months.

 

In 1991 I established a fruitful collaboration with F.Paresce and M.Clampin, at that time both at the STScI, to build a new type of optical coronograph27,37,38 for alt-azimuthal telescopes, characterized by a de-rotating pupil mask. We successfully operated the coronograph in several runs at the NTT and WHT telescopes9,58,59,62. My main technical contribution was the development of the control system, especially complex for the real-time control of the rotation of the apodizer (in practice, a compact telescope pointing model to calculate the parallactic angle). The collaboration with F. Paresce extended to the use of his previous coronograph at the 2.2m Calar Alto telescope. In addition to being extremely fruitful scientifically4,6,8,57,60,64, this activity put me for the first time in contact with the MPIA team in Heidelberg.

In 1992 I contacted R. Lenzen at MPIA to partner in a team to respond to the first call for proposals for VLT instrumentation. I lead my Torino group in the CONICA collaboration, with responsibility for the detector electronics. We were the first Italian team to participate in the development of VLT instrumentation. As a co-investigator, I strengthened my ties with the MPIA while struggling to keep Torino in the project despite the lack of adequate national, non-capital, funding (most of the national resources were allocated to the Galileo telescope). In view of repeated failures to secure the necessary funds, I decided to leave Italy and in 1995 I moved to Heidelberg. 

 

At MPIA I was appointed as scientific and technical leader of the MAX camera29,40, a superb thermal infrared camera for UKIRT. MAX was based on a Rockwell 128×128 Si:As BIB detector tailored for high flux, low noise performance. The MAX design presented many advanced features, including all-reflective, aspheric, diffraction limited optics oversized to easily accommodate larger arrays, a hybrid (liquid helium plus closed cycle cooler) cryogenic system, and a powerful read-out electronics based on a VME-bus system and a Super-Sparc work station. I lead the construction of MAX, from the concept to the design and construction phase, working on issues such as stray-light rejection, filter specifications, optical alignment strategy, and the data acquisition SW, rapidly developed from the version used on the other MPIA near-IR cameras. The commissioning and acceptance tests in Tucson were completed 8 days before the first night on UKIRT, in November 1995. In the very first night MAX provided excellent images with an unprecedented combination of sensitivity and spatial resolution. As soon as we got MAX in focus and the pupil aligned, Alpha Tau showed a spectacular diffraction pattern and I counted up to the 11th diffraction ring, a moment that I cannot forget. After the completion of the telescope upgrade program in August 1996 with the tip-tilt secondary mirror, MAX routinely reached diffraction and background  limited imaging between 5 and 25μm, with astonishing sensitivity. Between 1995 and 2000 I have spent a significant fraction of my time on Mauna Kea, and more than 120 nights at the telescope, gaining a unique experience on IR observations and on the operations of a major facility. My duties ranged from scheduling to proposal evaluation, calibration, general user support on data reduction, dewar maintenance, installation and alignment at the telescope, major electronics repair at the 4200m of the summit, even solving, with a redesign of the original LHe vessel, a complex cryogenic problem with thermoacustic oscillations triggered when the camera was oriented in given directions. To contribute to the safety of my coworkers on the summit and increase schedule flexibility I toke a CPR certification. Almost every night I also operated the other UKIRT instruments (CGS4, IRCAM3, UFTI), as service observing for a great variety of scientific programs.

The MAX/UKIRT combination has set the state-of-the-art in ground-based mid-IR astronomy. The advent of mid-IR cameras at 8-10m class telescopes, however, makes mid-IR astronomy with 4m class telescopes much less attractive, due the enormous gain of observing efficiency with larger telescope diameters (~D4) for instrument operating in diffraction and background limited conditions. For this reason, MAX was decommissioned in early 2001, when it still was in perfect operating conditions. The technical legacy of MAX can be found in the mid-IR instruments built by C. Telesco at the University of Florida.

 MAX has been scientifically very productive, with many papers published on referred journals by various teams. In Heidelberg I started to collaborate scientifically with S. Beckwith, thus my research with MAX concentrated on dust disks in pre-main sequence stars, and more recently on the Orion Cluster (for details see the “Research Accomplishments” section).

In Heidelberg I also contributed to the ISOPHOT calibration, exploring the behavior of the internal Fine Calibration Source(s) (FCS) with respect to various parameters like temperature, orbital position, and filters. For the P1 detector (1-16μm) I found the first evidence for a significant increase of the detector responsivity at the lowest flux levels, an unexpected effect which since then has been carefully studied by the ISOPHOT team. The necessary correction is now part of the standard ISOPHOT data reduction pipeline.

Finally, in Heidelberg I also contributed to the definition studies of the LBT and VLTI/MIDI interferometers, and I am still part of the MIDI science working group.

 

In 1999 I took an ESA position and moved to the STScI in Baltimore. I joined the HST project as Instrument Scientist for WFC3, with main responsibility for the newly approved IR channel with its new type of HgCdTe detectors. A panchromatic two-channel camera covering from the UV to the near-IR, WFC3 will be installed during the next Servicing Mission 4 onboard the HST31. The IR channel is equipped with a new type of 1K×1K infrared detector, dubbed WFC3-1R, developed by Rockwell Science Center. It has an unusually high operating temperature, T=150K, and long cutoff wavelength at 1.7μm to keep the dark current low.

As a WFC3 Instrument Scientist I have worked on a variety of topics. For example, on the estimate of the thermal background at the focal plane of the IR channel (a crucial parameter to define the maximum tolerable dark current, and therefore the detector band-gap), revising the previous estimates of the HST background as measured with NICMOS32. My analysis led to a new model for the HST emissivity budget (basically I find that the dust on the primary mirror has a poor thermal coupling with the mirror surface), and solved a longstanding discrepancy between models and NICMOS measures. Recent post-refurbishment NICMOS data are in excellent agreement with my predictions and the new model is now part of the latest generation of exposure time calculators. I also worked on CCDs, contributing mostly to the definition of unusual operating modes, such as the implementation of the charge injection, that we expect to use late in the emission to recover the losses of charge transfer efficiency due to radiation damage. Part of this and other work is documented in a number of WFC3 Instrument Science Reports73-84.

 

However, for four years my main duty has been to direct (at STScI) or advise (at NASA/Goddard) a team of about 20 scientists doing laboratory activity on the selection and characterization of flight detectors. We have tested several tens of prototypes and candidate flight parts, both for performance and for reliability under thermal, mechanical and radiation effects in space environment. The work organization and schedule of the activities has been one of my top priorities. Our main goal in this phase was to obtain the most rapid and reliable estimate of the performances, to provide Rockwell with the immediate feedback needed for further optimizations. Our operations were constrained by various requirements, e.g. all test procedures had to be defined in observance of the NASA rules for the handling of flight parts, as well as work orders, log keeping, etc. A significant amount of my time has been also devoted to the management of the human resources, especially in what concerns the harmonization of the STScI and NASA/Goddard teams, in more than one occasion at the edge between collaboration and competition. Also the different nature of my official role within the two groups forced me to be extremely flexible and use a variety of managerial styles, namely assertive and nurturing with my STScI people, strategic with the Goddard staff.

The long days spent at Goddard have given me a unique opportunity to become familiar with the development methods of NASA. In addition, the collaboration with industry,  Rockwell Science Center for the detector production and Ball Aerospace for the construction of the optical bench, has been extremely interesting. The participation to a large number of internal meetings with a variety of goals (technical, status review, planning, contract, advisory, etc…) has refined my understanding of the issues typical of business-oriented organizations, and exposed me to a variety of managerial styles and ways to approach and solve problems. To be part of these environments is uncommon for a non-US citizen, and I had to obtain special permissions from the US State Department.

The production of suitable flight parts matching the original specifications has turned out to be much harder than Rockwell originally expected. This has been the highest risk factor in the entire 85M$ WFC3 project. My program had therefore the highest visibility and scrutiny from NASA headquarters, also because the SNAP mission, a proposed space telescope of 2 m diameter with ultra-wide field aimed to the discovery of a large number of cosmological Type 1a supernovae, is planning to use the same detectors. I routinely presented the results of the program to the WFC3 Scientific Oversight Committee, to members of NASA headquarters, and to the international community33,34. This experience has greatly helped me refine my ability to deliver authoritative speeches and perform under stress and heavy exposure. The two flight parts, prime and spare, have finally been down-selected on May, keeping the instrument within budget and schedule. This activity has been explicitly commended by NASA in the last evaluation of the STScI performance, and gained me the 2002 Excellence Prize from STScI.

 

I regard the experience on WFC3 as a large step ahead compared to my previous work, which was more focused on planning, building, commissioning, and using new instruments in small, university level, teams. Working on WFC3 has given me a unique experience on the construction and test of Hubble instrumentation, new detector development, space qualification processes, etc. Moreover, the complexity of the task, the variety of environments and different organizations has exposed me to much higher levels of responsibility, and greatly refined my own project management skills and capabilities as team leader.

 

At the STScI I have the privilege of contributing to one of the most successful projects of modern Astronomy, in an extremely demanding and rewarding scientific environment. Having successfully accomplished my major milestones, I am willing to consider new challenging opportunities at your institution.

 SCIENTIFIC ACCOMPLISHMENTS

 

My scientific activity combines my two historical interests: construction and use of novel instrumentation and a longstanding curiosity about the interaction between stars and their circumstellar medium. I focussed most recently on star formation, in particular on the Orion Nebula and the Trapezium cluster. Previously I worked on a variety of related subjects, e.g. luminous blue variables and planetary nebulae, which I investigated with different observational techniques, or even theoretically.

In the following I will highlight relevant science themes that I have investigated. The research on the Orion Nebula is still ongoing and I intend to remain active in this field for the foreseeable future.

 

1. Research on the Orion Nebula

 

Our understanding of massive star formation is critically based on the nearest active region, the Orion Nebula (ON) and its associated stellar Cluster (ONC). According to the current paradigm, dense, rich clusters dominated by a few massive OB stars represent the most prolific Galactic star-forming environment. The ON is a harsh environment, characterized by winds and ionizing radiation, multiple outflows, close dynamical encounters and substantial X-ray emission. The canonical scenario developed in the last two decades for isolated low mass stars forming in sparse clusters like Taurus-Auriga may not adequately describe crucial aspects of the early stellar evolution. Disk evolution and planet formation processes, in particular, may be strongly affected in these conditions, with major implications on the probability of forming planets able to support life.

 

1.1) Mid-IR survey of proplyds (Ref. 67,69)

I started working on the Orion Region in 1997, using the MAX camera that I developed for the UKIRT telescope. The exquisite sensitivity of this instrument allowed me, in collaboration with Beckwith and Herbst, to perform the first mid-IR imaging survey of the Orion Nebula at 5 and 10 μm, that we complemented with 3.5 μm data taken with the UKIRT facility instrument IRCAM-3. In sub-arcsecond seeing conditions we probed 9 fields centered on prominent dark silhouette or externally photoionized (“proplyd”) sources, detecting thermal emission from a large fraction of all the catalogued objects falling within our fields. Absolute photometry indicates that mid-IR emission is generally in excess with respect to the stellar photosphere, allowing us to estimate a fraction of circumstellar disks in the Trapezium cluster larger than 80%, in agreement with the most recent estimates. We also found that standard disk models cannot explain, in several cases, the strong 10 μm excess that we observe, forcing us to consider new scenarios for the origin of the mid-IR emission.

 

 

1.2) Modeling the IR emission of disks in Orion (Ref.17)

To understand the cause of the strong mid-IR excess, in collaboration with Beckwith and Panagia, I modeled the infrared SED of circumstellar disks embedded in a HII region and photoevaporated by the external ultraviolet radiation.

First, we calculated the IR emission of a pre-main-sequence star surrounded by a dusty globule immersed within an HII region. We assumed the globule to be spherical, homogeneous, optically thin at IR wavelengths, and photoevaporated according to the classic Dyson model. Second, we considered the IR emission of a passive (non accreting) disk directly exposed to the same nebular environment, using and improving Chiang & Goldreich (1997) model. In the presence of a strong ionizing source, the opposite disk sides receive different amounts of radiation, therefore the flaring angle and the surface temperature distributions are different, resulting in well-distinct SEDs for the two disk faces. Finally, we consistently combined the globule and disk models to estimate the total IR emission of proplyds. The energy input from the central star and the nebular environment increases the disk flaring angle, and, therefore, also the amount of stellar radiation intercepted by the disk. In practice, the relative intensity of the disk vs. envelope emission varies with the tilt angle relative to the directions to θ1 Ori C and the Earth. We then explored the dependence of the SEDs upon the tilt angle with respect to the Earth, the distance from θ1 Ori C, the size of the envelope, the inner disk radius, and the temperature of the central star. The resulting SEDs are characterized by a broad peak of emission at 30-60 μm and are in general significantly different from those of isolated disks in low-mass starforming regions like Taurus-Auriga. Our model can account for the strong mid-IR excess we detected at 10 μm, and indicates that in the presence of an external radiation field, these relatively evolved Class 2 objects may display a SED peaking at mid-IR and far-IR wavelengths.

 

 

1.3) Mapping the Orion Nebula in the mid-IR (Ref. 71,72)

With MAX on UKIRT I started a second, major project aimed at building a map of the Orion Nebula core at 10 and 20μm with sub-arcsecond resolution. At these wavelengths the region remains largely unexplored, as previous investigations concentrated on the BN/KL and Trapezium/Ney Allen objects. Using standard chopping and nodding technique, we covered at both wavelengths an area ~5×3.5arcmin2 centered on the Trapezium region, scanning for four nights the field both in RA and DEC with different chopping amplitudes. Given the brightness of the region, chop/nod techniques with throw<30arcsec (the maximum allowed by the UKIRT secondary) produce images affected by strong artifacts. To recover the information, a new image reconstruction method had to be developed, as described in the next point. Our images reveal for the first time the detailed structure of the Orion Nebula in the mid-IR. Together with the Ney-Allen and BN/KL regions, we detect a variety of large scale features (filaments, knots, arcs…) tracing the overall structure of this blister-type HII region. We also detect approximately 170 point sources, most of them for the first time at mid-IR wavelengths, including sources with extremely red colors. These may represent a population of pre-main sequence stars, or even protostars more deeply embedded in the underlying OMC-1 molecular cloud. The availability of data taken at different epochs also allows us to find evidence of significant variability at 10μm.

 

 

1.4) Inversion methods for mid-IR imaging (Ref. 14,16,18, 21, 30, 41)

Working on the map of the Orion Nebula, I realized that an image restoration method for mid-IR images would have a major impact on wide-field imaging at these wavelengths. With Prof M. Bertero, an expert of image reconstruction and inversion problems at the University of Genova (Italy), we envisioned and developed an iterative reconstruction algorithm based on the projected Landweber method that computes, in the proper metric space, the smallest solution subjected to the constraint of positivity (real astronomical signals are always positive). The restored images exhibit artifacts related to the chopping amplitude and detector size, and we found that their nature and location can be predicted by analyzing the mathematical structure of the problem. We then performed a complete investigation of the performance, and limits, of this restoration algorithm using real chopped and nodded images, thus developing the data acquisition and data reduction strategy I finally used for the wide-field imaging of the Orion Nebula.

We have then extended our investigation to the case of targets surrounded by a suitable region of empty sky, a condition that in principle can always be met by mosaicing adjacent images up to the field edges. In this situation, the problem can be treated with Fourier-based techniques and a different iterative method can be used, namely a relaxed and projected version of the van Cittert method. Our most recent study shows that the same problem can be reduced to the inversion of a non-singular positive definite matrix whose eigenvalues and eigenvectors can be explicitely calculated, allowing to implement an iterative algorithm converging to the unique non-negative least-square solution.

 

 

 

1.5) HST study of the mass accretion rates in Trapezium Cluster (Ref. 91)

The relevance of accretion processes in the Trapezium Cluster has not yet been explored. Using the Wide Field Planetary Camera 2 onboard the Hubble Space Telescope I have observed the core of the Orion Nebula in the U- and B-bands. A preliminary analysis of isolated single stars (thus neglecting binaries and extended proplyd sources for which more refined PSF photometry is needed) allowed to obtain aperture photometry for 91 stars in the U-band (F336W) and 71 stars in the B-band (F439W). With my collaborators, I also searched the archive of WFPC2 images for complementary V-band (F547M) and I-band (F791W) photometry. We then extracted a primary sample made of 12 sources having complete WFPC2 UBVI photometry and known spectral type between K8 and M5.5 from Hillenbrand (1997). We located each star on the HR diagram considering both the standard ISM reddening law with RV=3.1 and the ``anomalous'' reddening law with RV=5.5,  which is more appropriate for the Orion Nebula, together with two different bolometric corrections, given the uncertainties at these spectral types. We find that the RV=5.5 reddening law provides the smallest scatter in age and a HR diagram nicely compatible with Palla and Stahler model. With one possible exception, all sources show excess luminosity in the U-band, that we attribute to mass accretion. The known correlation between the U-band excess and the total accretion luminosity, recalibrated to our photometric system, allows us to estimate the mass accretion rates, which are found to be in the range 10-7-10-10M8y-1. Four stars lying on the 10-5 M8y-1 birth line of Palla & Stahler show mass accretion rates ~10-7M8y-1, indicating that the main accretion phase has been recently terminated. This relatively low mass accretion rate may be related to the development of the HII region generated by the Trapezium OB stars. If this is the case, the Initial Mass Function is affected by the evolution of the most massive cluster's stars, thus inducing an increment of low mass, “accretion aborted”, stars. This would be in agreement with the recent findings that the Orion Nebula presents a fraction of low mass stars and brown dwarfs that is roughly twice as high as that measured in Taurus- Auriga. Within our small primary sample, the mass accretion rates appear to decrease with the stellar age. We also find indication of a trend between the mass accretion rate and the stellar mass.

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1.6) Measuring the mass accretion rates in the Great Orion Nebula

Using the WFI on the ESO 2.2 m telescope, I have imaged in the U-band filter the Great Orion Nebula (~34´×33´) to measure the excess luminosity and obtain the mass accretion rates for hundreds of cluster members. The main goal of this project is to trace possible systematic differences in the mass accretion rates for similar stars located in different nebular environments, e.g. at different distances from the Trapezium stars. This can provide final measure of how the mass accretion rate is affected by the presence of nearby massive stars through the onset of UV flux, and confirm the hypothesis that this phenomenon may produce the departure of the IMF from the classical Salpeter spectrum at low masses observed in the Orion core. The data reduction is in progress at the moment of this writing.

    

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2. Research on Star Formation in low-mass associations

 

 

2.1) Disk evolution vs. binary formation: the DH/DI Tau system (Ref. 11)

Using MAX, Meyer, Beckwith, Herbst and I observed in 1997 two young stars in the Taurus dark cloud, DH Tau and DI Tau, spatially resolving for the first time their 10μm emission. The weak-emission T Tauri star DI Tau, which was tentatively identified by Skrutskie et al. on the basis of 12 μm IRAS data as an object in the process of dissipating its circumstellar disk, was found to have no infrared excess at a wavelength of 10 μm. The nearby classical T Tauri star DH Tau exhibits excess emission at 10 μm consistent with predictions based on circumstellar disk models. While both objects appear to have the same stellar mass, age, and rotation rate, they differ in two fundamental respects: DH Tau is a single star with an active accretion disk, and DI Tau is a binary system lacking such a disk. The companion to DI Tau has a very low luminosity and is located at a projected distance of ~20 AU from the primary. Assuming the system to be coeval, we derived a mass below the hydrogen burning limit for the companion. We speculated that the formation of a substellar mass companion has led to the rapid dissipation of the circumstellar disk that may have surrounded DI Tau.

 

 

2.2) The archetype: T Tau  (Ref. 8, 10, 66)

My first observations of T Tauri and its surrounding nebula (Burnham nebula) were made in 1994 using both the STScI coronograph at Calar Alto (Spain) and the STScI-Torino alt-az coronograph at ESO-NTT in Hα6563, [SII]6716-6731 and relative 6670/80 satellite continuum filters. Taking advantage of the subarcsec seeing conditions, my coworkers and I mapped the circumstellar environment down to 2" from the star, corresponding to 320A.U. at the T Tauri distance of 160pc. Both the Hα and [SII] images revealed a complex morphology, characterized by several clumps of shock-excited gas superimposed on large scale continuum emission. In particular, we detected a jet-like feature departing from the immediate surroundings of the star in a southly direction that leads to a region of shock excited clumps. A curved filament departs also from this region, crossing Burnham nebula up to the previously known Herbig-Haro object HH A of Schwartz (1990). The south-western part of Burnham nebula is characterized by a number of small, nearly circular clumps and we found a faint, isolated HH object in the northern part of the nebula. Taking into account all the available data, we suggested that an optical jet is ejected by T Tau S roughly along the plane of the sky. The jet at first moves into the neutral components originating the shock excited knots and then impacts the edges of the cavity associated to the outflows. The jet wiggling due to the orbital motion of the emitting source and/or to precession phenomena could explain the peculiar excitation status of the Burnham nebula.

Herbst, Beckwith, and I returned in 1997 to this source taking near-infrared Fabry-Perot images and low and high resolution long-slit spectroscopy data. The FP images, taken in the v=1-0 S(1) line of molecular hydrogen, reveal a complex system of almost twenty interlocking loops and arcs within 10" of the central stars. These structures are almost certainly shocks, with the H and K band spectra indicating a range of excitation temperatures and velocities. The interaction with the ambient molecular cloud of two, almost perpendicular outflow systems can explain the complex molecular hydrogen morphology of T Tau. Such flows may be collimated by circumstellar disks.

On UKIRT we also obtained spatially resolved near and mid-infrared photometry of the binary, finding evidence for disks in both stars, with a strong silicate absorption line in the infrared companion and an emission feature in the primary. Separating the primary and companion fluxes allowed a reinterpretation of published variability measurements to give an inclination angle of the T Tauri system of 19º.

 

 

 

2.3) Discovery of new jet in the Serpens molecular cloud (Ref. 12,65)

Herbst, Beckwith, and I have discovered a new molecular hydrogen outflow in the Serpens molecular cloud. Narrowband filter images taken in the 2.12 μm ν=1-0 S(1) transition of H2 and adjacent continuum reveal a series of bright knots of pure line emission apparently emerging to the north-northwest from the embedded source SMM-3 and passing close to the visible star CK-8. Low-resolution H- and K-band spectra of the region show more than a dozen distinct H2 transitions, whose strength ratios point to shock heating with Texc ~ 2000 K. Echelle spectra of the S(1) transition with 20 kms-1 resolution reveal unusual kinematics: the line center velocity increases linearly with distance to the north-northwest from SMM-3 until the bright knots of emission, at which point the velocity begins dropping to a fraction of its maximum value. The molecular hydrogen emission likely arises in limb-brightened bow shocks as a jet from SMM-3 encounters the ambient molecular cloud. This scenario is strengthened by recent HCO+ and SiO submillimeter observations of SMM-3, which show an apparent outflow corresponding to the H2 structures.

 

2.4) ISO-PHOT observations of circumstellar disks (Ref. 22)

I contributed to an extensive ISO research program lead by S. Beckwith on the study of the structure and evolution of circumstellar disks. Using ISO-PHOT we observed 97 stars in five young clusters at 25 and 60 μm to determine the frequency of infrared emission from circumstellar disks. The clusters have ages between 1 and 300 Myr. Most stars (~80%) that have near-infrared excess emission, thought to be indicative of accretion disks, exhibit far-infrared emission; only one object that has no excess emission in the near-infrared exhibits far-infrared excess emission. No stars older than 10 Myr have evidence for optically-thick disks. These results showed that dust in the disks between about 0.3 and 3 AU disappears on timescales of ~ 10 Myr, identical within the uncertainties to the timescale for cessation of accretion as indicated by near-infrared observations of similar samples. Detection of one object whose dust optical depth is intermediate between opaque and transparent suggests that the duration of the transition phase between optically-thick and thin disk emission is less than 300,000 yr. Broad-band photometry between 2.5 and 100 μm, low resolution spectra between 2 and 12 μm, and 200 μm maps of 18 young stars (1-3 Myr old) in the Taurus and Chamaeleon dark clouds suggests that the irradiation dominates over viscous dissipation of mass accretion in the heating of the disk. The spectral energy distributions are consistent with those predicted by models of disks heated centrally by the stellar/accretion photosphere or by scattering from a diffuse halo surrounding the disk. The observations demonstrate that heating by accretion through the disks contributes little or no power to the energy budget at distances more than a few tenths AU from the central star.

 

2.5) The formation of a massive protostar: IRAS20126+4104 (Ref. 15)

I participated in an multi-wavelength research program lead by R. Cesaroni on the source IRAS 20126+4104. We obtained line and continuum observations at 1.3 mm and 3.5 mm with the Plateau de Bure interferometer, from 350μm to 2 mm with the James Clerk Maxwell telescope, and at 10 and 20μm with MAX on UKIRT. The results confirm that IRAS 20126+4104 is a very young stellar object embedded in a dense, hot core and lying at the centre of a rotating disk. The bipolar jet first imaged Cesaroni et al. (1997) in the 2.122μm H2 line is seen also in the SiO(2-1) transition, which allows to study the velocity field in the jet. We developed a simple model to obtain the inclination angle of the jet (and hence of the disk axis), which turns out to be almost perpendicular to the line of sight. By studying the diameter of the disk in different transitions and the corresponding line widths and peak velocities, we demonstrated that the disk is Keplerian and collapsing, and computed the mass of the central object and the accretion luminosity. We showed that if all the mass inducing the Keplerian rotation is concentrated in a single star, then this cannot be a ZAMS star, but more likely a massive protostar which still derives most of its luminosity from accretion.

 

 

 

 

 

 

3. Research on Hot Luminous Stars and LBVs

 

3.1) AG Carinae  (Ref. 4)

I led a theoretical investigation of the past evolutionary history of the Luminous Blue Variable AG Carinae on the basis of the standard dynamical model for the interaction of a hot stellar outflow with a slower wind from an earlier evolutionary phase. We showed that a continuous mass loss is a most viable mechanism by which the star can produce the observed massive shell of ionized gas and dust. In particular we estimated a typical mass loss rate 1-4×10-4 M¤ yr-1 and a terminal wind velocity V in the range 20-40 km/s for the 'pre-LBV' phase. These values allow us to locate the AG Car precursor in the yellow-supergiant region of the HR diagram.

 

3.2) HR Carinae  (Ref. 9)

In collaboration with a team lead by M. Clampin, I performed multicolor coronographic imaging and optical spectroscopy of the LBV HR Car. Our images revealed the presence, in both Hα and [NII] filters, of a filamentary nebula characterized by a bipolar, nearly point-symmetric structure, similar to some well-known planetary nebulae. The nebular filaments, which extend to 18˝ from the star, appear to originate from a central brighter compact structure which envelopes HR Car, ~8˝ size. From the emission line flux, we estimated the total mass of ionized gas in the nebula to be ~2.1 M¤. We also found evidence for the presence of intrinsic polarization from the change of polarization at the Hα emission line with respect to the continuum. This result implies that the distribution of the scattering material situated close to the star is not spherically symmetric, and indicates that the asymmetries on the small distance scale, as revealed by spectropolarimetric observations, agree with the large scale morphology, as revealed by coronographic imaging.

 

 

3.3) HD 168625  (Ref. 13)

T. Herbst and I obtained the first images of the mid-IR emission from the nebula surrounding the Galactic luminous blue variable (LBV) HD 168625. With MAX on UKIRT we obtained four images, centered at 4.7, 10.1, 11.6, and 19.9μm, plus a Br-γ image with IRCAM3. On the basis of the available spectrophotometric data and of our photometry of the central star, we revised the distance currently assumed for this source from 2.2 to 1.2 kpc. The dust emission, which is optically thin and therefore sensitive to the mass distribution, clearly indicates the bipolar structure of the nebula. The bulk of the infrared (IR) flux comes from a geometrically thin layer of dust tracing the outer edges of the nebular lobes. An inner shell or ring along the equatorial plane is also detected. From the mid-IR spectral energy distribution we constrained the composition and temperature of the grains. Through a simple geometrical model we estimated the dust density and total mass in the shell. Considering the structure of the nebula from an evolutionary point of view, we investigated the formation mechanism (novalike ejection vs. interacting stellar winds) and the recent past of the LBV precursor. We found that the interaction of the present wind with a slower dusty wind (M¤ yr-1; v km s-1) ejected by the stellar precursor in a previous phase is by far the most viable formation mechanism for the nebula around HD 168625. Finally, we discussed the general occurrence of an evolution to the red side of the HR diagram for the LBV precursors.

  

4. Research on Planetary Nebulae

 

4.1) NGC7027  (Ref. 6)

With my collaborators, I performed narrow band, optical line imaging of the young planetary nebula NGC 7027 in sub-arcsecond seeing conditions at the Calar Alto 2.2m telescope. In all our filters, centered on the Hα-6563, Hβ-4861, [NII]-6583, and [OIII]5007 lines and in a 6670/80 Hα continuum band, the nebula shows a complex clumpy structure whereas the central star is well resolved in the continuum band.  We obtained a very accurate map of the local extinction up to AV = 5 and estimated for the exciting source mV = 16.60 +/- 0.15, leading to Tstar approximately equal to 220,000 K and Lstar approximately equal to 4,700 solar luminosity. Correcting our images for extinction, the true annular structure of the planetary nebula was for the first time revealed at optical wavelengths. We could definitely confirm that the optical maximum corresponds to a 'hole' in the dust distribution. We tracked the ionization status of the nebula, finding evidence for a complex scenario.

 

 

 LIST OF PUBLICATIONS

 

Referred journals

 

1)     A Search for Non Stellar Contribution to the Optical and Near-IR Flux of RS CVn binaries. I. The cases of TY Pyx, UV Psc, RU Cnc and VV Mon

M.Busso, F.Scaltriti, P.Persi, M.Robberto, G.Silvestro, 1987.

Astronomy Astrophysics, 183, 83.

 

2)     IRAS Sources Associated with Nebulosities Resembling Herbig-Haro Objects

P.Persi, M.Ferrari-Toniolo, M.Busso, M.Robberto, F.Scaltriti,

G.Silvestro, 1988.

The Astronomical Journal, 95(4), 1167.        

 

3)     A Search for Young Stellar Objects in Southern Dark Clouds

P.Persi, M.Ferrari-Toniolo, M.Busso, L.Origlia, M.Robberto,

F.Scaltriti, G.Silvestro, 1989.

The Astron. Journ., 99(1), 303.

 

4)     Evidence for a yellow-supergiant phase for AG Carinae

M.Robberto, A.Ferrari, A.Nota, F.Paresce

Astronomy Astrophysics, 269, 330 (1993)

 

5)     Evidence from infrared observations of circumstellar matter around chromospherically active binaries

F.Scaltriti, M.Busso, M.Ferrari-Toniolo, L.Origlia, P.Persi,

M.Robberto, G.Silvestro

Mon.Not.R.Astron.Soc. 264, 5 (1993)

 

6)     High-resolution imaging of NGC 7027

M.Robberto, M.Clampin, S.Ligori, F.Paresce, H.J.Staude

Astronomy Astrophysics 280, 241 (1993)

 

7)     TIRCAM: a Mid-Infrared camera for ground-based astronomy

P.Persi, M.Ferrari-Toniolo, A.R.Marenzi, M.Busso, L.Corcione,

A.Ferrari, M.Gai, G.Nicolini, F.Racioppi, M.Robberto, G.Bonazzola,

K.Shivanandan, G.Tofani

Experimental Astronomy, 5, 363 (1994)

Erratum: Experimental Astronomy, 6, 293 (1995)

 

8)     Coronographic imaging of T Tauri: discovery of an optical jet in Burnham's nebula

M.Robberto, M.Clampin, S.Ligori, F.Paresce, V.Sacca`, H.J.Staude

Astronomy Astrophysics 296, 431 (1995)

 

9)     High resolution coronographic imaging and spectropolarimetry of the HR Carinae nebula

M.Clampin, R.E. Schulte-Ladbeck, A. Nota, M.Robberto, F.Paresce,     

G.C.Clayton, The Astronomical Journal, 110,251 (1995)

 

10) Wind-Disk-Ambient Cloud interactions in the Near Environment of T Tauri

T.M.Herbst, M.Robberto, S.V.W.Beckwith

Astron.J., 114, 744 (1997)

 

11) The Transitional Pre-Main-Sequence Object DI Tauri: Evidence for a Substellar Companion and Rapid Disk Evolution

M.R.Meyer, S.V.W.Beckwith, T.M.Herbst, M.Robberto

Ap.J.489, L173 (1997)

 

12) A New Molecular Hydrogen Outflow in Serpens

T.M.Herbst, S.V.W.Beckwith, M.Robberto

Ap.J.Lett., 486, L59 (1997)

 

13) Warm dust around blue-hypergiants: mid-IR imaging of the LBV HD168625

M.Robberto. T.M.Herbst

Ap.J., 498, 400 (1998)           

 

14) An inversion method for the restoration of chopped and nodded images

M.Bertero, P.Boccacci and M.Robberto

Inverse Problems, 15, 345 (1999)

 

15) Unveiling the disk-jet system in the massive (proto)star IRAS 20126+4104

R.Cesaroni, M.Felli, T.Jennes, R.Neri, L.Olmi, M.Robberto, L.Testi

and C.M.Walmsley

Astron.Astrophys, 345, 949 (1999)

 

16) Wide-Field Imaging at Mid-Infrared Wavelengths: Reconstruction of Chopped and Nodded Data

Bertero, M.; Boccacci, P.; Robberto, M.

The Publications of the Astronomical Society of the Pacific, 112, 1121 (2000)

 

17) The Infrared Emission of Circumstellar Envelopes, Dark Silhouettes, and Photoionized Disks in H II Regions

Robberto, M., Beckwith, S. V. W., Panagia, N.

ApJ, 578, 897 (2002)

 

18) A Fourier-based method for the restoration of chopped and nodded images

Bertero, M., Boccacci, P., Custo, A., De Mol, C., Robberto, M .

Astronomy & Astrophysics, 406, 765 (2003)

 

19) Low Mass Pre-Main Sequence Stars in the Large Magellanic Cloud – II: Accretion rates from HST-WFPC2 Observations

Romaniello, M., Robberto, M . , Panagia, N.

Astronomy & Astrophysics, submitted (2003)

 

20) High-Resolution Mid-Infrared Observations of the Giant Star Forming Region W51

S.Ligori, Robberto, M., Herbst, T. M.

Astronomy & Astrophysics, submitted (2003)

 

21) Inversion of second-difference operators with applications to infrared astronomy

Bertero, M., Boccacci, P., Robberto, M .

Inverse Problems, submitted (2003)

 

 

Invited reviews

 

22) ISO-PHOT Observations of Circumstellar Disks around Young-Stellar-Objects

M.Robberto, S.V.W.Beckwith, M.R.Meyer and A.Natta

Proc. of ESA Conf. "The Universe as seen by ISO", P. Cox and M. F. Kessler Editors, ESA SP-427, p. 195 (1999)

 

23) Understanding Star Formation with the NGST

Robberto, M., Beckwith, S. V. W.
The Institute of Space and Astronautical Science Report SP No. 14, p. 11-18 (2001)

 

24) Infrared Astronomy with the Hubble Space Telescope and the Next Generation Space Telescope

Robberto, M.

Memorie SAIt, 74, 230 (2003)

 

 

Books

25) The design and Construction of Large Optical Telescopes

P. Y. Bely Ed., Springer, (2003)

[Main contributor for IR telescopes and instruments]

           

 

SPIE proceedings

 

26) First results with TC-MIRC (Two Channel Medium InfraRed Camera)

M.Robberto, M.Gai, M.D.Guarnieri, S.Ligori, S.Marta, G.Nicolini,

L.Pellino, F.Paresce, F.Racioppi

Proc. SPIE Symposium "Instrumentation in Astronomy VIII",

D.L.Crawford, E.R.Craine eds., SPIE Proc. Vol.2198, p. 446 (1994)

 

27) Stellar coronograph for the New Technology Telescope

M.Clampin, F.Paresce, M.Robberto

Proc. SPIE Symposium "Instrumentation in Astronomy VIII",

D.L.Crawford, E.R.Craine eds., SPIE Proc. Vol.2198, p. 172 (1994)

 

28) A transputer network for real-time acquisition of IR astronomical data

M.Gai, M.D.Guarnieri, M.Robberto, L.Pellino, F.Paresce

Proc. SPIE Symposium "Instrumentation in Astronomy VIII",

D.L.Crawford, E.R.Craine eds., SPIE Proc. Vol.2198, p. 962 (1994)

 

29) MAX: the new MPIA thermal infrared imager

M.Robberto and T.M.Herbst

Proc. of SPIE Vol.3354 "Infrared Astronomical Instrumentation",

A.M.Fowler ed., 711 (1998)

 

30) An inversion method for the restoration of chopped and nodded images

M.Bertero, P.Boccacci and M.Robberto

Proc. of SPIE Vol.3354 "Infrared Astronomical Instrumentation",

A.M.Fowler ed., 877 (1998)

 

31) Wide Field Camera 3 for the Hubble Space Telescope

Cheng, E. S., Hill, R. J., MacKenty, J. W., Cawley, L., Knezek, P., Kutina, R. E., Lisse, C. M.; Lupie, O. L.; Robberto, M., Stiavelli, M. O'Connell, R. W., Balick, B., Bond, H., Calzetti, D., Carollo, M.; Disney, M., Dopita, M., Frogel, J., Hall, D. N., Hester, J., Holtzman, J., Luppino, G. A., McCarthy, P., Paresce, F., Saha, A., Silk, J., Trauger, J. T., Walker, A., Whitmore, B., Windhorst, R., Young, E. T.

 Proc. SPIE Vol. 4013, 367(2000)

 

32) Performance of HST as an infrared telescope

Robberto, M., Sivaramakrishnan, A., Bacinski, J. J., Calzetti, D., Krist, J. E., MacKenty, J. W., Piquero, J.; Stiavelli, M.,

Proc. SPIE Vol. 4013, 386(2000)

 

33) Infrared Detectors for WFC3 on the Hubble Space Telescope

Robberto, M., Baggett, S. M., Hanley, C., Hilbert, B., MacKenty, J. W., Cheng, E. S., Hill, R. J., Johnson, S. D., Malumuth, E. M., Polidan, E.,  Waczynski, A., Wen, Y., Haas, A, Montroy, J. T., Piquette, E., Vural, K., Hall, D. N. B.

Proc. SPIE Vol. 4850, 121 (2002)

available at http://www.stsci.edu/instruments/wfc3/wfc3-docs.html

 

34) Selection of the Infrared Detectors for Wide Field Camera 3 on the Hubble Space Telescope

Robberto, M., Baggett, S. M., Hilbert, B., MacKenty, J. W., Stiavelli, M., Kimble, R. A., Hill, R. J.,Cottingham, D. A., Delo, G., Johnson, S. D., Landsmanm, E. M., Malumuth, E. M., Polidan, E., Russel, A. M., Waczynski, A., Wen, Y., Haas, A, Montroy, J. T., Piquette, E., Vural, K., Cabelli, C., Hall, D. N. B.

Proc. SPIE Vol. 5167-19 (2003)

           

 

Conference contributions: instrumentation

 

35) The 10 μm infrared camera TIRCAM

A.Ferrari, E.Anderlucci, M.Busso, L.Corcione, G.Nicolini,

M.Robberto, F.Scaltriti, P.Persi, G.Farina, M.Ferrari-Toniolo,

A.Preite-Martinez, M.Ranieri, G.Tofani, S.Gennari, F.Lisi,

G.Marcucci, P.Salinari, M.Sozzi, G.Bonazzola, D.Crosetto, M.Gai,

S.Monticelli, G.Silvestro, K.Shivanandan, 1989.

Memorie S.A.It - Vol.60 - N.1-2, p.247.

 

36) TC-MIRC: a Two Channel Medium IR Camera

M.Robberto, M.Gai, G.Bonazzola, L.Corcione, A.Ferrari, S.Gennari,

G.Nicolini, F.Paresce, F.Racioppi

Proc. ESO Conference on "Progress in Telescope and Instrumentation         

Technologies", Garching, 27-30 April 1992. M.-H. Ulrich Ed., ESO

Conference and Workshop Proceedings No.42, p.709 (1992)

 

37) A Coronograph for the NTT

M.Clampin, F.Paresce, G.De Marchi, M.Robberto, A.Ferrari, S.Marta

Proc. ESO Conference on "Progress in Telescope and Instrumentation         

Technologies", Garching, 27-30 April 1992. M.-H. Ulrich Ed., ESO

Conference and Workshop Proceedings No.42, p.713 (1992)

 

38) A stellar coronograph for the NTT: first result and performance

M.Clampin, M.Robberto, F.Paresce

in "Circumstellar dust disk and planet formation", R.Ferlet and

A.Vidal-Madjar eds., Edition Frontieres, p.351 (1994)

 

39) Drift Scanning Survey Spectrograph:L DS3

M.Gai, M.G.Lattanzi, M.D.Guarnieri, M.Robberto, U.Munari,

Proceedings of the 2nd Conference of the Working Group of IAU

Commission 9 on ``Wide-Field Spectroscopy",

Athens, 20-25 May, 1996, Kluwer Academic Publishers, pp. 121-122 (1996)

 

40) Thermal IR imaging with MAX: pushing the limits of single-dish

ground based observations

M.Robberto, T.M.Herbst, S.V.W.Beckwith, C.Birk, P.Bizenberger

Proc. ESO Workshop on “Science with VLT”, F. Paresce ed.,

Springer-Verlag, p. 391 (1997)

 

41) Image restoration in thermal infrared astronomy

M. Bertero, P. Boccacci and M. Robberto, 1999, 

Proc. Second Workshop on "Large-Scale Scientific Computations", M.Griebel, S. Margenov, and P. Yalamov eds., Notes on Numerical Fluid Mechanics, Vol. 73, p.250 (1999)

 

 

 

 

 

Conference contributions: science

 

42) Mechanical Energy Release by Protostars and Molecular Clouds

G.Silvestro and M.Robberto, 1985.

Proc. "Plasma Astrophysics", Varenna, ESA-SP 207, p.235.

 

43) On the Line Profile of Shell Shaped Bipolar Outflows

G.Silvestro and M.Robberto, 1987.

Proc. IAU Symposium Nr.122 "Circumstellar Matter", D. Reidel, p. 87.

 

44) Near-IR Observations of the SSV13, SSV9, SSV5 Sources in NGC 1333

M.Busso, P.Persi, M.Robberto, F.Scaltriti, G.Silvestro, 1987.

Proc. IAU Symposium Nr.122 "Circumstellar Matter", D. Reidel, p. 113.

 

45) An Outflow Model for Bipolar Planetary Nebulae and the Case of NGC 6302

G.Silvestro and M.Robberto, 1987.

Proc. Frascati Workshop "Planetary Nebulae", Reidel, p. 107.

 

46) On VLBI Observations of SN 1987A and a New Calibration of the Extragalactic Distance Scale

G.Silvestro and M.Robberto, 1987.

Proc. "ESO Workshop on SN 1987A", Garching, p. 619.

 

47) IRAS and near IR observsations of active binaries

F.Scaltriti, M.Busso, P.Persi, L. Origlia, M.Robberto, G.Silvestro, 1987.

Proc. 5th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun

Colorado Univ., p.89, 1987

 

48) On the Instability Time-Scale of the Outflow Associated with the

HH 7-11 Chain

G.Silvestro, M.Busso, P.Persi, M.Robberto, F. Scaltriti, 1987.

Proc. "10th European Regional Meeting of the IAU", Prague, Vol.4,

p. 25.

 

49) IRAS and Near-Infrared Observations of Peculiar Nebulosities

P.Persi, M.Busso, M.Ferrari-Toniolo, L.Origlia, M.Robberto,

F.Scaltriti, G.Silvestro, 1988.

Proc. Second Torino Workshop "Mass Outflows from Stars an Galactic

Nuclei", Kluwer, p. 337.

 

50) Evidence of Thin Dust Shells in Some RS CVn stars

F.Scaltriti, M.Busso, M.Robberto, P.Persi, G.Silvestro, 1988.

Proc. Second Torino Workshop "Mass Outflows from Stars an Galactic

Nuclei", Kluwer, p. 325.

 

51) A Thin-Shell Model for Molecular Outflows

M.Robberto and G.Silvestro, 1988.

Proc. Second Torino Workshop "Mass Outflows from Stars an Galactic

Nuclei", Kluwer, p. 321.

 

52) Dust Envelopes and IR Excesses in a Sample of RS CVn-Type Binaries

F.Scaltriti, M.Busso, L.Origlia, M.Robberto, P.Persi, G.Silvestro,

1988.

Proc. IAU Colloquium N.107 "Algols", Victoria (Canada) 15-19

August 1988, Ed. A.H.Batten, Kluwer Academic Publishers, P.362

(1989).

 

53) A Search for Young Stellar Objects in Southern Dark Clouds

P.Persi, M.Ferrari-Toniolo, M.Busso, L.Origlia, M.Robberto,

F.Scaltriti, G.Silvestro, 1989.

Proc. 3rd National Conference “Infrared Astronomy”, Gallipoli,

19-22 September 1989.

Memorie S.A.It. - Vol.61 - N.1, p.67 (1990)

 

54) On the Origin of Circumstellar Shell around RS CVn-type Bynaries

M.Busso, F.Scaltriti, M.Ferrari-Toniolo, L.Origlia, P.Persi,

M.Robberto, G.Silvestro, 1990.

Proc. 3rd National Conference "Infrared Astronomy", Gallipoli,

19-22 September 1989.

Memorie S.A.It. - Vol.61 - N.1, p.77 (1990)

 

55) CCD Images of nebular Sources in star forming regions

L.Origlia, M.Busso, M.Ferrari-Toniolo, P.Persi, M.Robberto,

F.Scaltriti, G.Silvestro, 1990.

Proc. 3rd National Conference "Infrared Astronomy", Gallipoli,

19-22 September 1989.

Memorie S.A.It. - Vol.61 - N.1, p.95 (1990)

 

56) Polarimetry and CCD Imaging of Herbig Ae/Be stars and Star Forming Regions

F.Scaltriti, V.Piirola, M.Robberto, M.Busso, 1990.

Proc. NATO Advanced Research Workshop "Angular Momentum Evolution

of Young stars", Noto (Italy), 17-21 September 1990. S.Catalano and

J.R.Stauffer Eds., Kluwer Academic Publishers, p.109 (1991)

 

57) Nebular line imaging of NGC 7027

M.Robberto

Memorie S.A.It. - Vol.64 - N.3, p.698 (1993)

 

58) High Resolution Coronographic Imaging and Echelle Observations of S119: a new Luminous Blue Variable?

A.Nota, L.Drissen, M.Clampin, C.Leitherer, A.Pasquali, C.Robert,

F.Paresce, M.Robberto

Proc. 34th Herstmonceux Conference "Circumstellar Media in Late

stages of stellar evolution", Cleigg, Meikle and Stevens Eds.,

Cambridge University Press, p. 89 (1994)

 

59) Multi-color observations of the beta-Pictoris circumstellar disk

M.Clampin, M.Robberto, F.Paresce, A.Maccioni

in "Circumstellar dust disk and planet formation", R.Ferlet and

A.Vidal-Madjar eds., Edition Frontieres, p.67 (1994)

 

60) A search for a circumstellar disk around 68 Ophiuchi

S.Ligori, M.Clampin, F.Paresce, M.Robberto, H.J.Staude

in "Circumstellar dust disk and planet formation", R.Ferlet and

A.Vidal-Madjar eds., Edition Frontieres, p.377 (1994)

 

61) Near infrared imaging of the southern HII region RCW38

S.Ligori, A.Moneti, M.Robberto, M.D.Guarnieri, H.Zinneker

Memorie della Societa` Astronomica Italiana, 65, 815 (1994)

 

62) Multi-color coronographic imaging of the Beta Pictoris disk

M.Clampin, F.Paresce, M.Robberto, A.Maccioni

Astrophys.Space.Sci. Vol.224, No.1-2, p.399 (1995)

 

63) Optical coronography at Calar Alto: discovery of a jet from T Tauri   

M.Robberto, M.Clampin, S.Ligori, F.Paresce, V.Sacca`, H.J.Staude

in "Disk and outflows around young stars", S. Beckwith,

J. Staude, A. Quetz and A. Natta eds, p.637 (1996)

 

64) Line imaging of NGC 7026

M.Robberto, S.Ligori, M.Stanghellini, D.Thompson

Proc. IAU Symp. 160 "Planetary Nebulae",  H. J. Habing and

H. J. G. L. M. Lamers eds., Kluwer Academic Pub., p.275 (1997)

 

65) A new molecular hydrogen outflow in Serpens

T.M.Herbst, S.V.W.Beckwith, M.Robberto

Proc. IAU Symp. 182 "Low Mass Star Formation from Infall to Outflow", 

p.135 (1997)

 

66) Molecular and Atomic Shocks in the Near Environment of T Tauri

T.M.Herbst, M.Robberto, S.V.W.Beckwith

Proc. IAU Symp. 182 "Low Mass Star Formation from Infall to Outflow", 

p.135 (1997)

 

67) Circumstellar Disks in Orion: First Results from a Mid-IR survey

M. Robberto, S. V. W. Beckwith, Herbst, T. M.

Star Formation 1999, Proceedings of Star Formation 1999, Editor: T. Nakamoto, Nobeyama Radio Observatory, p. 231(1999)

 

68) Mid-IR Images of W51

S. Ligori, M. Robberto, T. M. Herbst

Star Formation 1999, Proceedings of Star Formation 1999, Editor: T. Nakamoto, Nobeyama Radio Observatory, p. 377(1999)

 

69) Mid-IR emission of Circumstellar Disks in the Orion Nebula

Robberto, M., Beckwith, Panagia, N. , Herbst, T. M., Ligori, S., Bertero, M., Boccacci, P., Custo, A.

The Origin of Stars and Planets: the VLT view, ESO Astrophysics Symposia, J.F. Alves and M. J. McCaughrean Eds., Springer, on CD-ROM (2002)

 

70) Thermal IR imaging of W51-IRS2

Ligori, S., Herbst, T. M., Robberto, M.,

Hot Star Workshop III: The Earliest Stages of Massive Star Birth. ASP Conference Proceedings, Vol. 267. Edited by Paul A. Crowther, p.383 (2002)

 

71) Mid-IR Imaging of the BN/KL Region

Robberto, M., Beckwith, S. V. W., Ligori, S., Herbst, T. M., Custo, A., Boccacci, P., Bertero, M.

Proc. Ionized Gaseous Nebulae, a Conference to Celebrate the 60th Birthdays of Silvia Torres-Peimbert and Manuel Peimbert, Mexico City, November 21-24, 2000 (Eds. W. J. Henney, J. Franco, M. Martos, & M. Peña) Revista Mexicana de Astronomía y Astrofísica, Vol. 12, pp. 40-40 (2002)

 

72) The Orion Nebula Cluster at Mid-IR Wavelengths

Robberto, M.,

Proc. Modes of Star Formation and the Origin of Field Populations, ASP Conference Proceedings, Edited by Eva K. Grebel and Walfgang Brandner., Vol. 285., 68 (2002)

 

 

Space Telescope Science Institute Internal Reports

 

73) WFC3 Near IR-Channel: PSF and Plate Scale Study

M. Stiavelli, C. Hanley and M. Robberto,

Instrument Science Report WFC3 1999-01, Space Telescope Science Institute (1999)

 

74) The NICMOS Exposure Time Calculator: Algorithms and User Interface

A. Sivaramakrishnan, S. Jolfeltz, M. Sosey, B. Simon, M. Robberto,

Instrument Science Report NICMOS 2000-01, Space Telescope Science Institute (1999)

 

75) First Results from the New HgCdTe MBE Detectors for WFC3 - IR Channel
M. Robberto, L. Cawley, C. M. Lisse, and B. Hill
Instrument Science Report WFC3 2000-04, Space Telescope Science Institute (2000)

 

76) Encircled Energy Measurements for the M10 WFC3 1R-MUX Pinhole Images - Set 1
C. Hanley, M. Robberto
Instrument Science Report WFC3 2001-11, Space Telescope Science Institute (2001)

 

77) Encircled Energy Measurements for the M10 WFC3 1R-MUX Pinhole Images - Set 2
C. Hanley, M. Robberto
Instrument Science Report WFC3 2001-14, Space Telescope Science Institute (2001)

 

78) Performance of the HI-101 IR Detector Measured Using the MPIA System
I.Dashevsky, M. Robberto
Instrument Science Report WFC3 2001-15, Space Telescope Science Institute (2001)

 

79) Optimization of the WFC3 Cold Stop Mask
M. Giavalisco, M. Stiavelli, and M. Robberto
Instrument Science Report WFC3 2001-16, Space Telescope Science Institute (2001)

 

80)  IR Data Pipeline Using Fowler Sampling
I. Dashevsky, C. Hanley, M. Robberto
Instrument Science Report WFC3 2001-19, Space Telescope Science Institute (2001)

 

81) The WFC3 Exposure Time Calculators: Functionality and Operations
C. Hanley, C. Lisse, P. Knezek, Olivia Lupie, Massimo Robberto, and Jenica Nelan
Instrument Science Report WFC3 2000-02, Space Telescope Science Institute (2002)

 

82) The reference pixels on the WFC3 IR detectors
M. Robberto, C. Hanley, I. Dashevsky
Instrument Science Report WFC3 2002-06, Space Telescope Science Institute (2002)

 

83) Masking Technique on WFC3-IR Images
B. Hilbert, S. Baggett, M. Robberto
Instrument Science Report WFC3 2003-06, Space Telescope Science Institute (2003)

 

84) Performance of the WFC3-IR channel with FPA#64
M. Stiavelli and M. Robberto
Instrument Science Report WFC3 2003-05, Space Telescope Science Institute (2003)

 

 

AAS Meeting  Abstracts

 

85) New observations of Beta Pictoris circumstellar disk with the NTT coronograph

M.Clampin, F.Paresce, M.Robberto

Bull.Am.Ast.Soc., Vol.25, No.2, p.903 (1993)

 

86) S119: a new luminous blue variable?

A.Nota, C.Leitherer, M.Clampin, L.Drissen, A.Pasquali, C.Robert,

F.Paresce, M.Robberto

Bull.Am.Ast.Soc., Vol.25, No.2, p.909 (1993)

 

87) HST/WFPC2 image of the Orion Nebula in the U and B bands

Robberto, M., Beckwith, S. V. W., Makidon, R. B., Panagia, N.

American Astronomical Society Meeting 198, #48.12  (2001)

 

88) Testing of HgCdTe Devices For WFC3

Hill, R.J., Waczynski, A., Polidan, E.J., Krebs, D.J., Robberto, M.,

Johnson, S.D.,

BAAS Vol. 31, No. 5, 1512 (2000)

 

89) HST Wide Field Camera 3 Progress Report

MacKenty, J. W., Cheng, E., Hill, R., Cawley, L., Hanley, C., Henry, R. L., Knezek, P., Lisse, C., Lupie, O., Robberto, M., Stiavelli, M.

American Astronomical Society Meeting 196, #32.08 (2000)

 

90) Detailed Performance of IR Detectors for WFC3

Hill, R.J., Waczynski, A., Wen, Y., Johnson, S.D., Polidan, Malumuth, E.,

Robberto, M.

AAS 202, 401R (2003)

 

91) Performance of the FC3-IR flight detectors

Robberto, M., Baggett, S. M., Hilbert, B. N., MacKenty, J.W., Stiavelli, M., Hill, R.J., Waczynski, A., Wen, Y., Johnson, S.D., Polidan, Malumuth, E., Kimble, R. A.

AAS 202, 403R (2003)

 

92) First results from an HST study of the Mass Accretion Rates in the Trapezium Cluster

Song, J., Robberto, M., Beckwith, S. V. W., Makidon, R. B., Panagia, N.

 AAS 202, 2804S (2003)

 

 

Other

 

93) Osservazioni astronomiche nell'infrarosso termico: il progetto TIRCAM

M.Robberto, Tesi di Dottorato,

Universita` di Torino (1989)