0Assigned ID: 2860
----- Attempting Submission 1 (Wed Mar 23 08:38:01 GMT 2022) -----
HST Phase I Proposal 2860 successfully submitted.
Receipt: # 2860-1
----- Attempting Submission 2 (Thu Mar 24 19:01:02 GMT 2022) -----
HST Phase I Proposal 2860 successfully submitted.
Receipt: # 2860-2
----- Attempting Submission 3 (Fri Mar 25 20:00:02 GMT 2022) -----As agreed I updated all coordinates with the latest astrometry derived using the more recent Hubble observations (GO-15354) to take into account possible proper mostions using Gaia DR3 as reference frame.
Therefore all coordinates, magnitudes, and Orient constraints changed slighlty. This does not impact the target visibility nor the exposure time.
We discovrerd that target O8.5V is actually two stars. We therefore changed to O9V-1 as primary target in the slit to ensure proper centroiding and recaluclated the total count rates under the assumption that both stars are O9V stars (most likely they are of later type).
This does not violate the safty limits.-2132448531----- Attempting Submission 1 (Thu Jul 07 20:27:23 GMT 2022) -----
----- Attempting Submission 2 (Thu Jun 08 23:17:13 GMT 2023) -----Far out in the SMC wing: the extraordinary cluster NGC 602NGC 602 is a truly extraordinary young star cluster (YSC): located in a very low-density, low-metallicity region in the SMC Bridge it has formed a remarkable stellar content of 10^3 Solar masses and hosts many OB stars similar to Orion. Optical and infrared Hubble and Spitzer observations revealed a large number of disk-bearing, young stars in the cluster center and newly forming Young Stellar Objects embedded in the surrounding clouds. This suggests an age ladder for NGC 602 and that the massive OB stars drive star formation into the clouds. We are proposing to use the unique UV capabilities of Hubble to measure the far-ultra violet (FUV) fluxes and stellar winds of the 12 most massive cluster stars using STIS spectroscopy.
Only with HST, it is possible to directly access the FUV flux budget of the entire YSC, to quantify the stellar winds for the most massive O stars. Together with scheduled Cycle 1 Webb data we will establish how efficiently NGC 602 drives star formation outwards, which may lead to an extended star formation period, and how the close proximity to the OB stars influences protoplanetary disk and planet formation and evolution. Furthermore, scheduled VLT/MUSE integral field spectroscopy will enable us to directly study how the FUV fluxes shape the surrounding gas of the HII region. NGC 602, which has a mass budget similar to Orion but is located in a sub-solar metallicity environment, provides the link between star formation and feedback processes under Milky Way conditions, where YSCs are too heavily attenuated for FUV observations, and those in lower-metallicity environments like distant galaxies, where only the most massive stars can be resolved.We plan to observe 11 O and B stars in NGC 602 using STIS FUV MAMA spectroscopy.
To calculate the exposure times we used the SpTs of Ramachandran+2019 (obtained with optical VLT/FLAMES spectra). For the remaining two stars we estimated their SpTs using their F555W magnitudes in conjunction with the Castelli-Kurucz spectral atlas. We used the archival STIS data of Sk183 to verify our assumptions and to ensure that we do not exceed the safety limits of the MAMA detector (30,000 counts/s). To fulfill our science goals, we target a S/N>20 at a reference wavelength of 1500 Angstrom under the condition of not using more than one orbit per star.
To avoid undersampling, hot pixels, and to minimize the effects of cosmic rays, we plan to use the STIS-ALONG-SLIT dither strategy with four pointings and a shift of 11 spectral pixels (0.267 arcsec) as recommended by the Cycle 30 STIS instrument handbook (Prichard+ 2022).
Where possible we plan to observe always two stars per pointing. We want to use the G140L grating with the 0.5 arcsec, which is a good compromise between spectral purity, defined by the slit width, and to ensure that the two sources fall into the same slit, despite the Hubble pointing inaccuracies. The cluster center is relatively crowded so we plan to do target aquesition on the O3V star (Sk183) with a relative offset to each source. We used the exisiting HST ACS/WFC photoemtry for the target coordinates in the Gaia system (ICRS). We also used these coordinates to calulate the orients as well as the offsets needed to fit two stars in the same slit if applicatable.
The visit packing will be the following:
STIS-OFFSET-A (visit 28) (1 orbit): The stars O9V-2 and B0.7V will be observed with the same slit. Their estimated combined global count rate is 3,464 counts/s. Star B1.5(IV)e will be observed in
a separate exposure within this visit.
STIS-OFFSET-B (visit 29) (3 orbits): The stars O9V-3 and B2.5V will be observed with the same slit. Their estimated combined global count rate is 2,413 counts/s. The stars B2V-1, B2V-2, and B2V-3
will be observed in separate exposures within this visit.
STIS-OFFSET-C (visit 31) (3 orbits): The stars O8.5V and O9V-1 will be observed with the same slit. Star O9V-2 may fall in the same slit. Their combined global count rate is 7,828 counts/s. The
star O7V will be observed in separate exposures within this visit.Dr. Peter Zeidler is a photometry expert, especially for HST data, specifically WFC3 and part of the JWST NIRSpec ESA science operation team. He has studied the young massive star cluster Westerlund 2 in great detail and published multiple papers about it. He is also an expert in optical IFU spectroscopy, especially VLT/MUSE, where he leads multiple surveys. He is the PI of the successful JWST NIRCam and MIRI proposal to study the PMS stars and YSOs in NGC 602, the proposed target (GO-2662) as well as the VLT/MUSE proposal to study the same cluster's gas and stellar kinematics. He is also a Co-I of "GULP: Galaxy UV Legacy Project" an HST legacy project obtaining NUV imaging of 27 star forming galaxies.
Dr. Elena Sabbi is an expert in high-precision photometry, especially using WFC3, and studying resolved young star clusters in the Local Group. She published multiple papers on Magellanic star clusters, including the proposed target and was PI of the Hubble Tarantula Treasury Program mapping 30 Dor in the UV, optical, and near-infrared. She is PI of successful optical HST follow-up observations to determine the stellar binary fraction in the proposed target cluster and Co-I of the successful JWST and MUSE proposal for NGC602. She also got awarded 88 orbits as PI for "GULP: Galaxy UV Legacy Project" a treasury project obtaining NUV imaging of 27 star forming galaxies. She is the JWST NIRSpec team lead at STScI.
Dr. Antonella Nota is an expert in studying young star clusters photometrically and spectroscopically and has conducted multiple HST surveys of young, Local Group star clusters, such as Westerlund 2, NGC 346, and is PI of the complementary, optical HST data for NGC 602, the target we are proposing for. She is also Co-I of the successful JWST and MUSE proposal on NGC 602. She is also Co-I of "GULP: Galaxy UV Legacy Project" an HST legacy project obtaining NUV imaging of 27 star forming galaxies.
Dr. Daniel Lennon's field of interest are young massive stars. He is an expert in spectroscopy of OB stars in the FUV. He is Co-I in a proposal mapping the cluster core of R136 in 30 Dor spectroscopically with STIS in the FUV and complementing the dataset with UV photometry, similar to what we want accomplish with the proposed dataset.
Prof. Dr. Eva K. Grebel's field of expertise are resolved stellar populations as a tool for understanding star formation histories and galaxy evolution. She has worked extensively on star clusters of all ages in the Milky Way and in nearby galaxies, including very young star clusters, using both surveys as well as targeted observations. She is also Co-I of the successful MUSE proposal on NGC 602 and of "GULP: Galaxy UV Legacy Project" an HST legacy project obtaining NUV imaging of 27 star forming galaxies.
Dr. Monica Tosi focuses on resolved stellar populations, stellar population modelling, and the star formation histories of star clusters. She is also Co-I of the successful MUSE proposal on NGC 602.
Dr. Anna Pasquali's expertise is in spectroscopic studies of stellar winds, feedback processes in nebulae, and star cluster formation. She is also Co-I of the successful MUSE proposal on NGC 602.
Dr. Anna F. McLeod is an expert in photometric and spectroscopic studies of HII regions in the local Universe, particularly focusing on feedback processes and star-gas interactions. and Co-I of the successful JWST and MUSE proposal on NGC 602.Stellar Populations and the Interstellar Medium6falsetruefalsefalsefalsefalsefalseSUPPORTEDSTARMAIN SEQUENCE ONOThe coordinates are in the Gaia reference frameJ2000J2000STARMAIN SEQUENCE ONOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frameJ2000STARMAIN SEQUENCE ONOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame.
Originally we used the O8.5V star for the ACQ/PEAK but we discovered that this stars is actually two sources. We call them for now O8.5V_a and O8.5V_b. Hence we decided to center on the O9V-1 source instead. We adjusted the POS TARG offset accordinglyJ2000STARMAIN SEQUENCE ONOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frameJ2000STARMAIN SEQUENCE ONOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frameJ2000STARMAIN SEQUENCE ONOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frameJ2000STARB0-B2 V-IVNOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frameJ2000STARB0-B2 V-IVNOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frameJ2000STARB0-B2 V-IVNOThe coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frameJ2000STIS/FUV-MAMASpectroscopicNoNoG140L1425STIS/FUV-MAMASpectroscopicNoNoG140L1425STIS/FUV-MAMASpectroscopicNoNoG140L1425POS-TARGDITHER0.27LINEfalsefalse490.0STIS-ALONG-SLIT2falseThe scheduling data was generated by CASM 31.0.CASM was run in Phase II mode.The fixed orient is necessary tp fit two stars simulatniously in one slit. This method saves more 5 orbits in total1691710991000315.189547(Tic-Visit
:proposal-id 17223
:visit-id "28"
:proposal-version -1
:trans-version "20220630"
:date "08-Jun-2023 18:58:52.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "24"
:si-bright-earth-limb-angle 20.0
:data-volume 574544
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 17223
:visit-id "28"
:obset-id "28"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 17223
:visit-id "28"
:orbit-number 1
:pcs-time 393
:si-vis-utilization 3116
:al-overhead-at-end 0
:internal-dur-at-end 450
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3525
:pcs-gap 0
)true10The ETC Run # for the other star in the slit is:STIS.sp.1864808
The combined global count rate is: 4496 far below the saftly limits.The scheduling data was generated by CASM 31.0.CASM was run in Phase II mode.The fixed orient is necessary tp fit two stars simulatniously in one slit. This method saves more 5 orbits in total1696381325000340.089743(Tic-Visit
:proposal-id 17223
:visit-id "29"
:proposal-version -1
:trans-version "20220630"
:date "08-Jun-2023 18:58:30.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 3
:saa-model "24"
:si-bright-earth-limb-angle 20.0
:data-volume 1183456
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 17223
:visit-id "29"
:obset-id "29"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 17223
:visit-id "29"
:orbit-number 1
:pcs-time 393
:si-vis-utilization 3077
:al-overhead-at-end 0
:internal-dur-at-end 0
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3525
:pcs-gap 0
)
(Tic-Orbit
:proposal-id 17223
:visit-id "29"
:orbit-number 2
:pcs-time 392
:si-vis-utilization 3099
:al-overhead-at-end 128
:internal-dur-at-end 132
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3525
:pcs-gap 0
)
(Tic-Orbit
:proposal-id 17223
:visit-id "29"
:orbit-number 3
:pcs-time 392
:si-vis-utilization 2857
:al-overhead-at-end 128
:internal-dur-at-end 394
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3525
:pcs-gap 0
)true30The ETC Run # for the other star in the slit is: STIS.sp.1332724
The combined global count rate is: 5735 far below the safty limits.The scheduling data was generated by CASM 31.0.CASM was run in Phase II mode.The fixed orient is necessary tp fit two stars simulatniously in one slit. This method saves more 5 orbits in total1691234132000285.765083(Tic-Visit
:proposal-id 17223
:visit-id "31"
:proposal-version -1
:trans-version "20220630"
:date "08-Jun-2023 18:58:53.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "24"
:si-bright-earth-limb-angle 20.0
:data-volume 574528
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 17223
:visit-id "31"
:obset-id "31"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 17223
:visit-id "31"
:orbit-number 1
:pcs-time 393
:si-vis-utilization 2959
:al-overhead-at-end 0
:internal-dur-at-end 450
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3525
:pcs-gap 0
)true10The ETC Run # for the other star in the slit is: STIS.sp.1331332716
The combined global count rate is: 11421 far below the safety limits.The other potential sources in the slit are:
O8.5V_a (F555W=15.209): STIS.sp.1864812, 3449
O8.5V_b (F555W=15.645): STIS.sp.1864811, 2308
O9V-3 (F555W=15.543): STIS.sp.1864810, 2535
The total possible countrate is 11021 well below the safty limit