Scientific Category is a required field. Science Keywords: Select from 2 to 5 items. Wavelength is a required field. Wavelength is a required field. For G160M observations, please consult Chapter 9 of the COS Instrument Handbook to estimate overheads and the number of exposures per orbit, and consequently the correct lifetime position. Use of LP4 with G160M requires justification in the "Special Requirements" section of the Phase I PDF. Use of the default LP6 with G160M requires no justification. Proposals can be submitted with the warning present. 0 Assigned ID: 3878 ----- Attempting Submission 1 (Fri Nov 25 15:13:38 GMT 2022) ----- Joint XMM/HST For the best data quality, it is generally required to use all four FP-POS positions when observing at a given COS cenwave. See the COS Instrument Handbook for exceptions that may apply to observations with G130M/1291 or G160M. Schedulability set to 100. -579517184 ----- Attempting Submission 1 (Mon Dec 19 22:35:25 GMT 2022) ----- HST Phase II Proposal 17274 successfully submitted. Receipt: # 17274-1 ----- Attempting Submission 2 (Tue Dec 20 16:22:15 GMT 2022) ----- We provide justifications for our choices of gratings, CENWAE, and FP-POS settings in the Proposal Description. NGC 3516 is a remarkable Seyfert-1 galaxy, which over the last decade has undergone major spectral transformations, classifying it as a changing-look AGN. Understanding the nature and origin of spectral variability in such changing-look AGN would provide key insights into the accretion-outflow mechanism. Swift monitoring of NGC 3516 shows dramatic flux rises and declines during its changing-look state. We propose ToO observations with XMM, NuSTAR, and HST, triggered using Swift monitoring, to catch NGC 3516 at a high flux level to be able to carry out the first high resolution X-ray and UV spectroscopy of its winds during the changing-look state. The proposed observations would enable us to ascertain the role of winds in the transformation of NGC 351 This is a HST ToO observation, approved as part of a joint ToO XMM-Newton proposal. It plans to obtain the HST/COS spectrum of NGC 3516 during its bright flux state of the changing-look state. The simultaneous COS UV spectrum of NGC 3516 is crucial for our investigation Please note that the agreement between XMM-Newton and HST missions allows one Disruptive HST ToO per cycle, which corresponds to this proposal. For confirmation of this you may contact the XMM mission PI (Norbert Schartel): Norbert.Schartel@sciops.esa.int In case another XMM ToO proposal triggers a Disruptive HST ToO, then this HST ToO observation becomes non-Disruptive. However, that is very unlikely because our XMM proposal was the only approved proposal requesting joint ToO observation with HST. Please note this ToO HST observation needs to be taken simultaneously with XMM-Newton (within 2 days). As stated in our proposal the ToO observations may be carried out any time within 14 days after the trigger request. The HST ToO observation will be triggered in one of the following windows, when the target is observable with XMM: 2023-05-01 to 2023-05-31 2023-09-21 to 2023-12-02 2024-03-17 to 2024-04-30. Our HST/COS time and setup is based on the prior observations of NGC 3516 and our simulations (described in the XMM proposal), which required 2 orbits to constrain broad absorption lines of Ly-alpha, N V, and C IV with gratings G130M and G160M. This also allows measurement of weak, low-ionization lines associated with the new ionization state of the warm absorber. Following the Phase II Proposal instructions and the allowed COS settings for Cycle 30, the central wavelengths and FPPOS positions that we have selected provide the optimum full spectral coverage of the interested regions with the G130M and G160M gratings, minimize spectral gaps, and maximize the potential of the detection of the relevant broad and narrow absorption lines. This enables us to fully explore the UV spectral signatures of the obscuring outflow in NGC 3516. Thus, for our observation we utilize G130M/1222, G130M/1291, G160M/1600, and G160M/1623. We obtained the required time for each exposure using the COS Exposure Time Calculator (ETC) tool and the NGC 3516 UV fluxes at 2030 A published by Mehdipour et al. 2022, ApJ, 925, 84. The redshift z=0.00973 and foreground extinction of E(B-V)=0.107 are taken into account. For the target acquisition we used the minimum expected UV flux of 0.7e-14 erg/cm^2/s/A and calculated the required exposure time to get a S/N of 30 using ACQ/IMAGE with BOA. Using the expected flux of 1.5e-14 erg/cm^2/s/A for the ToO, the exposure times were calculated to give a S/N of about 10 for each exposure with G130M/1222, G130M/1291, G160M/1600, and G160M/1623. The maximum UV flux observed (3e-14) does not pose a bright object risk for COS. NGC 3516 has been acquired and observed with HST COS before, and there are no bright field objects that would prove an overlight risk to COS. For the BUFFER-TIME, we obtained the recommended buffer (2/3 of the buffer fill time) from the ETC for each exposure. Please note because we are using two different CENWAVES with each grating and two FP-POS positions in each, we already accomplish the actual objectives of switching between different FP-POS settings: (1) Better science return: the spectrum is placed at four different locations on the detector, enabling us to detect and reject detector anomalies like dead spots, hot spots, grid-wire shadows, etc. (2) Spread the flux across the detector in multiple locations, especially in bright emission lines, to decrease charge depletion and extend the lifetime of the detectors. We do not want to sacrifice S/N with unnecessary extra exposures and increased overhead during each visit by using all 4 FP-POS settings with each CENWAVE. When only one CENWAVE is used, then 4 FP-POS settings makes sense, but that's not the case for our observations. Our chosen FP-POS settings reflect our S/N requirements while still meeting the objectives of using different FP-POS settings in our program. Although reduced gyro operations for HST would be unfortunate, our program would still remain fully feasible. Reduced gyro operations would approximately halve the opportunities for coordination with XMM-Newton. Also, any orientation limitation would not impact our program. Dr. Mehdipour has expertise in X-ray/UV spectroscopy of ionized outflows in AGN, optical-UV-X-ray continuum modeling, and photoionization modeling. He has previously led projects on the studies of ionized outflows in AGN with HST, Chandra, XMM-Newton, and Swift. Dr. Mehdipour will carry out the main analysis and modeling of the HST/COS spectrum. Dr. Kriss is an expert in multi-wavelength observations of AGN. He has vast experience in HST analysis and modeling of UV absorption lines of different types of AGN outflows. Dr. Kriss will provide advice on the analysis and modeling of the HST/COS spectrum. Prof. Kaastra is the lead developer of the SPEX code, which is used for X-ray spectroscopy and photoionization modeling. Prof. Kaastra has experience and expertise in the X-ray studies of AGN outflows. He led the discovery of the obscuring wind in NGC 5548 with a multi-wavelength campaign using XMM-Newton, NuSTAR, Chandra, Swift, and HST in 2013-2014. Prof. Kaastra will contribute to photoionization modeling of the new observation. Dr. Costantini is an expert in high-resolution X-ray spectroscopy of AGN using XMM-Newton and Chandra and has previously studied NGC 3516. She will provide advice on the analysis of new data. Dr. Brotherton has expertise in ground-based optical spectroscopic studies of AGN and will contribute to the optical analysis of NGC 3516. Supermassive Black Holes and Active Galaxies 6 false false false false false false SUPPORTED GALAXY ACCRETION DISK BLR SEYFERT WIND NO This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 COS/FUV Spectroscopic No No G130M 1222 COS/FUV Spectroscopic No No G130M 1291 COS/FUV Spectroscopic No No G160M 1600 COS/FUV Spectroscopic No No G160M 1623 1671553080370 The scheduling data was generated by CASM 30.3. CASM was run in Phase II mode. 1685169322000 108.94989622714769 (Tic-Visit :proposal-id 17274 :visit-id "01" :proposal-version -1 :trans-version "20220630" :date "20-Dec-2022 11:18:00.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 218064 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17274 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17274 :visit-id "01" :orbit-number 1 :pcs-time 393 :si-vis-utilization 2596 :al-overhead-at-end 0 :internal-dur-at-end 2421 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2989 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17274 :visit-id "01" :orbit-number 2 :pcs-time 392 :si-vis-utilization 2597 :al-overhead-at-end 0 :internal-dur-at-end 480 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2989 :pcs-gap 0 ) true 2 0 Using NGC 3516 minimum flux (corresponding to our ToO) of 0.7e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve target acquisition with S/N of 30. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G130M. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G130M. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G130M. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G130M. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G160M. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G160M. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G160M. Using NGC 3516 expected ToO flux of 1.5e-14 erg/cm2/s/A at 2030 A (Mehdipour et al. 2022), we calculated the exposure time to achieve S/N of about 10 with G160M.