0 0 ----- Attempting Submission 1 (Thu Jan 23 12:15:49 GMT 2025) ----- ----- Attempting Submission 2 (Thu Jan 23 19:18:21 GMT 2025) ----- ----- Attempting Submission 3 (Wed Mar 12 14:22:14 GMT 2025) ----- Cyg X-1 is a bright nearby source, located in a complex dusty region. Its dust grains and gas characteristics differ from the average of the diffuse medium, providing unique insights into dust in a star and planets forming site. Using the high-resolution of XMMNewton-RGS we will characterise the chemistry, size and abundance of interstellar dust around the oxygen spectral region, fundamental to determine the silicate contribution to the dust composition. Using the joint HST-STIS observation we will model the extinction curve and carbon features, giving unique insight on the dust size distribution and carbon content along this line of sight. Note: this HST observation is a joint observation via an XMM-Newton proposal. The HST observation does not need to be strictly simultaneous with the XMM observation. A reaction time of 1 week has been proposed, however a longer response time is also doable without loss of science information. A longer response time may be in fact necessary as the visibility windows of HST and XMM do not perfectly overlap. If the XMM observation is triggered when there is no HST window available, it is fine if the target is observed by HST at the next possible occasion (1-3 months away, depending on when this happens during the cycle). In the proposal we indicated 1 HST orbit, using G430L, G750L and G230L. However, the U band=9.38, is too bright for G230L (as written in the proposal). This will cause the G230L to saturate and instead we need to use E230M. For G430L and G750L we take 10 second exposures at 3 nod positions along the slit (nods needed to fully sample spectrum). SNR here is 200+ per exposure at R=500. Finally, we take CCDFLATs in occultation time to allow correcting of detector fringing. For the E230M the central wavelength 2415 A covers 1985 A to 2820 A which includes the 2175 A absorption feature and adjacent continuum. At the deepest part of the feature (2175A) the SNR is 2.8 per resolution element (R=30000). Binning to R=500 gives SNR 21 per exposure. Two exposures will be collected with MAMA (two iterations without nodding) so the SNR will be even higher. Acquisition will take place with neutral density filter to avoid saturation. Bright Object Limit has been verified with archival SWIFT UVOT photometry. Renormalizing our reddened O9V star model with these photometric points remains safely within the Bright Object Limits for MAMA, even with the brightest observed photometry in Cyg X-1's high-state (0.051 Jy at 2246 Angstrom; https://etc.stsci.edu/etc/results/STIS.sp.1952842/). Dr. Elisa Costantini is a senior research scientist at SRON, Netherlands Institute for Space Research. She is expert in high-resolution spectroscopy of gas and dust features and modeling of the ISM, in the UV and X-ray band. She also leads a large campaign in experimental measurements of interstellar dust. Dr. Sascha Zeegers (research fellow at ESA ESTEC) is an infrared and X-ray astronomer (theoretical and observational), with expertise in multiwavelength interstellar dust models and observations. She investigates the properties of interstellar dust, e.g. dust composition, crystallinity and dust size distributions and performs laboratory experiments on interstellar dust analogues in the X-rays. Dr. Ioanna Psaradaki is a Chandra Postdoctoral Fellow at the MIT Kavli Institute, specializing in the chemical evolution of our Galaxy and the properties of cosmic dust grains. Her expertise lies in X-ray and UV spectroscopy of the interstellar medium, as well as in laboratory studies of interstellar dust. Dr. Missagh Mehdipour (research scientist at the Space Telescope Science Institute) is experienced in joint X-ray and UV spectroscopic studies of AGN winds. He has expertise in photoionization modeling of winds and modeling the spectral energy distribution of AGN. Dr. Daniele Rogantini is a M. Burbidge Fellow at the University of Chicago with expertise in high-resolution X-ray spectroscopy. His research spans a wide range of astrophysical phenomena and objects, including active galactic nuclei, interstellar dust and gas, and X-ray binaries. Dr. Gilles Otten is a researcher at ASIAA. He is an expert of optical-infrared instrumentation and data reduction. Note: this co-I was added in Phase 2. This inclusion has been approved by Claus Leitherer at STSci. Stellar Populations and the Interstellar Medium 6 false false false false false false false true SECONDARY XMM_NEWTON 096431 false SUPPORTED STAR LMXB NO This object was generated by the targetselector and retrieved from the SIMBAD database. SIMBAD listed proper motion for this target. When retrieving targets with PM from SIMBAD, APT requests the coordinates be calculated with an epoch of the year 2000. Do not modify this epoch. Always review coordinates using the Target Confirmation tool, which graphically displays the PM. J2000 J2000 U band=9.38 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/CCD Spectroscopic No No G430L 4300 STIS/CCD Spectroscopic No No G750L 7751 POS-TARG DITHER 0.5327175 CCD nodding pattern with 3 positions, each step equivalent to 10.5 pixels which allows improving spectral resolution, preventing aliasing from undersampling and reduced impact of detector artefacts. LINE false false 3 90.0 STIS-ALONG-SLIT 1 false 1740513542677 The scheduling data was generated by CASM 33.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 17900 :visit-id "01" :proposal-version -1 :trans-version "20241217" :date "25-Feb-2025 20:59:02.0" :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 451440 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17900 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17900 :visit-id "01" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2659 :al-overhead-at-end 0 :internal-dur-at-end 688 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3039 :pcs-gap 0 ) true 1 0 Note that we are close to saturation on the acquisition with default aperture F28X50LP (t_sat = 0.14 sec and minimum exposure time 0.1 sec). So we use aperture F25ND3 with 1 second integration and S/N = 88 to be on the safe side. MAMA saturates in G230L (this grating was originally suggested in the proposal). For this target MAMA can only be used with the high and medium res echelles without having to resort to the ND gratings to prevent saturation in the worst case (brightest) scenarios. The CCD with G230LB would create issues with scattered light from the red end of the spectrum. We don't need the full spectral resolution so we can use 6x0.2 or 0.2x0.2 apertures. Aperture 0.2x0.2 minimizes order-order contamination. We do not need to PEAKUP with these apertures which saves a lot of time. SNR = 10.5 per resolution element per 223s integration time per pointing at 2500A. SNR = 2.8 (per resolution element) at 2175 A (STIS.sp.1952839). Double the amount of integration time in the two iterations. We can only fit one wavelength setting in this orbit. So we pick 2415A which covers 2175 A and the adjacent continuum (1985 A to 2820 A). Worst case (brightest flux in UV from SWIFT UVOT): https://etc.stsci.edu/etc/results/STIS.sp.1952842/ is still within safe limits. SNR 192 per 10 second pattern position. With 3 pointings in this pattern we have 30 seconds integration. CR-SPLIT = 2 (default) provides some safety against cosmic ray hits. SNR 270 per 10 second pattern position. Total integration time 30 seconds. CCDFLAT is needed to correct for fringes in the reddest part of G750L and taken during the occultation time with default integration times. A reduced slit width of 52x0.1 is used to be more like a point source. It is unclear if a square aperture would yield even better fringe correction.