Science Keywords: Select from 2 to 5 items. Science Keywords is a required field. 0 Assigned ID: 2561 ----- Attempting Submission 1 (Wed Sep 15 12:18:17 GMT 2021) ----- Joint Chandra/HST A couple of notes: 1) I added FLASH=20 for F275W observations. Please check. 2) I center the target (a trio of three galaxies packed) at WFC1 and UVIS1 to avoid the gap. Please let me know if you have any Qs. Thanks! Ming 825742513 ----- Attempting Submission 1 (Tue Oct 12 15:56:25 GMT 2021) ----- The brightest central galaxies (BCGs) are the largest and the most massive galaxies in the universe. Their origin is still under debate but major mergers should play a key role. While there have been several dramatic examples of local BCGs forming via dry mergers, BCGs are believed to mainly form with wet major mergers at high z and there has not been a local analog of such systems. We have searched for BCGs forming via wet major mergers in the local universe and have found a spectacular example of a trio of star forming galaxies with comparable luminosities and within 15 kpc from each other. We propose joint Chandra/HST observations to study AGN, ULXs, diffuse X-ray emission and mergers in this rare system. The results will shed light on the important early stage of BCG formation. We will observe IRAS 15205+5021 with three filters F275W, F475W and F814W in two orbits to study their central AGN, the merger signature between three central galaxies (like the tidal features) and the young stellar population. F475W and F814W observations will be done in one orbit with ACS/WFC, while the F275W observation will be done in another orbit with WFC3/UVIS. The ACS data in two high-throughput filters allow detections of faint features (e.g., individual star cluster associations, dust) and a detailed color map of the three galaxies. The F275W data will add important information on the SF in the last several 10^7 years and the F275W - F475W color is a very good age indicator. n/a Galaxies 6 false false false false false false false false SUPPORTED GALAXY INTERACTING GALAXY MULTIPLE NUCLEI STARBURST YES J2000 J2000 ACS/WFC Imaging No No F475W ACS/WFC Imaging No No F814W WFC3/UVIS Imaging No No F275W POS-TARG DITHER 3.034 LINE false false 2 85.29 ACS-WFC-DITHER-LINE 1 false POS-TARG MOSAIC DITHER 2 2.4 WFC3-UVIS-MOS-DITH-LINE false true 0.119 3 85.754 POS-TARG WFC3-UVIS-MOS-DITH-LINE 33.606 2 false 1634053798075 /tmp/OPVisit4000439318654760408.xml The scheduling data was generated by CASM 29.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 16845 :visit-id "01" :proposal-version -1 :trans-version "20210514" :date "12-Oct-2021 11:49:58.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1136896 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 16845 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 16845 :visit-id "01" :orbit-number 1 :pcs-time 383 :si-vis-utilization 2949 :al-overhead-at-end 0 :internal-dur-at-end 347 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3333 :pcs-gap 0 ) true 1 0 1634053798453 /tmp/OPVisit17604705565805297451.xml The scheduling data was generated by CASM 29.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 16845 :visit-id "02" :proposal-version -1 :trans-version "20210514" :date "12-Oct-2021 11:49:58.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 866240 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 16845 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 16845 :visit-id "02" :orbit-number 1 :pcs-time 383 :si-vis-utilization 2950 :al-overhead-at-end 127 :internal-dur-at-end 352 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3333 :pcs-gap 0 ) true 1 0