17447( 2) - 07-Sep-2023 18:16:15 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 17447 Version: 2 Check-in Time: 07-Sep-2023 18:16:15 STScI Edit Number: 0 Title Joint HST+XMM time-resolved UV+X-ray observations of a quasi-periodically erupting X-ray source ------------------------------------------------------------------------------------ Type Cycle GO 31 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Thomas Wevers Space Telescope Science Institute Y CoI: Dr. Dheeraj Pasham Massachusetts Institute of Technology N CoI: Riccardo Arcodia Massachusetts Institute of Technology N ------------------------------------------------------------------------------------ Abstract Quasi-periodic eruptions (QPEs) are recurrent, high-amplitude bursts of X-ray emission in the nuclei of galaxies hosting low mass (10^5-6 M_sun) black holes. Their nature is still hotly debated, with the main two model classes including various flavours of accretion disk instabilities, and two (or multi-)body interactions between the central SMBH and a stellar-mass perturber. The latter can involve a main sequence star, white dwarf, or stellar mass black hole, and the eruptions are variously related to tidal stripping of orbiting companions, Roche lobe overflow, or interactions of the perturber with an accretion disk. The main QPE properties are short recurrence times (2-20 hrs), short durations (27 min - few hrs) and high amplitudes (factor 10-100). Discovered and well studied in X-rays, the UV, IR and radio properties remain poorly constrained. We propose to obtain the first deep observations in the UV (currently constrained only with the XMM-Newton Optical monitor), with high cadence (3 min) HST FUV imaging of a QPE with eruptions lasting only 27 min and recurring every 114 min. These timescales are perfectly suited to perform the first time-resolved UV variability search during the X-ray eruptions. The HST spatial resolution will resolve out the host galaxy emission; with HST sensitivity in the FUV this will lead to a >2 orders of magnitude improvement compared to current constraints. A detection of UV variability and how it correlates with the X-rays will have field-defining implications that will redraw the theoretical landscape. Non-detections will provide very strong additional constraints on the geometry, extent and properties of the putative accretion disks. ------------------------------------------------------------------------------------ Observations Description ------------------------ HST/STIS/FUV-MAMA F25QTZ time-tag imaging observations of 1 target in 2 identical visits taken strictly simultaneous with XMM-Newton. This will be done through a 5-orbit contiguous visit, repeated twice. No time restrictions exist on the relative timing of the 2 visits in the cycle. We wish to obtain the highest possible time resolution, so use time-tag mode for imaging to fill the entire orbital visibility period. F25QTZ filter was chosen to obtain the lowest background with good sensitivity to FUV photons. Buffer times estimated from the ETC are > the orbital visibility time, so this has been set to 20000. ------------------------------------------------------------------------------------ 17447( 2) - 07-Sep-2023 18:16:15 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 ERO-QPE2 GALAXY, ACCRETION DISK, RA=02H34M48.7051S +/- 0.1", J2000 V = 18 galex FUV = 19.4 mag NUCLEUS DEC=-44D19'32.79" +/- 0.1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 17447( 2) - 07-Sep-2023 18:16:15 - [ 3] Visit: 01 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2614 S -MAMA G (2614 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ ERO-QPE2 1 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 1 N/A -MAMA G ERO-QPE2 2 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 2 N/A -MAMA G ERO-QPE2 3 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 3 N/A -MAMA G ERO-QPE2 4 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 4 N/A -MAMA G ERO-QPE2 5 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 5 N/A -MAMA G 17447( 2) - 07-Sep-2023 18:16:15 - [ 4] Visit: 02 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2614 S -MAMA G (2614 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 ERO-QPE2 STIS/FUV TIME-TA F25QTZ MIRROR BUFFER-TIME=20000 1 2796 S -MAMA G (2796 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ ERO-QPE2 1 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 1 N/A -MAMA G ERO-QPE2 2 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 2 N/A -MAMA G ERO-QPE2 3 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 3 N/A -MAMA G ERO-QPE2 4 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 4 N/A -MAMA G ERO-QPE2 5 STIS/FUV TIME-TA F25QTZ MIRROR none none none none 5 N/A -MAMA G 17447( 2) - 07-Sep-2023 18:16:15 - [ 5] Summary Form for Proposal 17447 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures F25QTZ ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BUFFER-TIME=20000 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names ERO-QPE2 ------------------------------------------------------------------------------------------------------------------------------------