Mapping the magnetospheric structure at outburst of the pre-main sequence close binary AK Sco

0 Assigned ID: 1528 ----- Attempting Submission 1 (Fri Mar 01 16:14:40 GMT 2013) ----- HST Phase I Proposal 1528 (gomezdecastro.apt) successfully submitted. 13372 COS + STIS observations of AK Sco APT file submitted by Kevin France on 06/24/13. File as approved by Ana Ines Gomez de Castro. Update 07/03/13 by kf, following CS email. Here are the changes that have been implemented : 1) STIS orbits were moved before the COS orbits, and the STIS orbits were split into two visits 2) Zero Phase (HJD) was taken from Alencar et al. 2003 and this was input into the visit level for the STIS visits, and used to calculate the starting phase for the STIS visits (01 and 02) 3) The COS observations (visit03) have been scheduled 13.55 – 13.61 days after the start of visit02 Updated by kf on 07/22/13: 4) STIS G230L buffer times adjusted to 200s per the advice of the CS. 1238806572 ----- Attempting Submission 1 (Mon Jun 24 13:25:49 GMT 2013) ----- ----- Attempting Submission 2 (Wed Jul 03 18:21:21 GMT 2013) ----- ----- Attempting Submission 3 (Mon Jul 22 22:36:05 GMT 2013) ----- Mapping the magnetospheric structure at outburst of the pre-main sequence close binary AK Sco Pre-main sequence (PMS) binaries are surrounded by circumbinary disks from which matter falls onto both components. The material dragged from the circumbinary disk flows onto each star through independent streams channelled by the variable gravitational field. The action of the bar-like potential is most prominent in high eccentricity systems made of two equal mass stars. AK Sco is a unique PMS system composed of two F5 stars that get as close as 11.3 stellar radii at periastron (e=0.47). AK Sco is an ideal laboratory to study matter infall in binaries and its role in orbit circularization. Our team has reported recently, the discovery of an unexpected 1.3mHz ultra low frequency (ULF) oscillation in the ultraviolet light curve at periastron passage. The oscillation lasted ~0.6% of the orbital period. According to our numerical simulations, the cirscumstellar structures get in contact at periastron producing an accretion outburst that triggered of the oscillation. If confirmed, this would unveil a new mechanism for angular momentum loss during pre-main sequence evolution and a new type of interacting binary. The objective of this project is to identify the source of the oscillation and the physical structure of the accretion flow before, during and after the oscillation is triggered. Since the accretion flow radiates in the ultraviolet range, this study requires an ultraviolet (UV) spectroscopic monitoring. AK Sco is a spectroscopic binary with period 13.609453 days and ephemeris for the phase. Phase = (JD-2446654.3634)/13.609453- INT(JD-2446654.3634) The target has to be visited twice, for 20,000 seconds each time. The two visits must be subsequent hence, if the first visit begins at T0, the second must begin at T0+13.609453days. During the FIRST VISIT the target has to be observed with COS, begining 10,000 before phase=0 and ending 10,000 after phase=0. All the observations need to be carried out in TIME-TAG mode. 7 orbits are to be spent in this first visit. Orbit 1: Star acquisition, instrument setting and then observations with G130M and G230M. Subsequent 6 orbits, AK Sco will be observed with G160M, G130M and G230M During the SECOND VISIT, AK Sco will be observed with STIS, starting 10,000 before the periastron passage (Phase0) and ending 10,000 after the passage. Again, 7 orbits are to be spent in this visit. Orbit 1: Acquisition and STIS set-up plus 6 sets of observations with G140L and G230L Subsequent 6 orbits: 8 sets of sort exposures with G140L and G230L will be obtained per orbit. AK Sco is schedulable from August 2 to October 20, 2013 and from January 25 to October 20, 2014. Assuming that the first scheludable dates are in September, the program could begin in: Sept 12, 2013, 19h:14m:47s UT, or in any date adding an entire number of 13.609453 days (13d 14h 37m 37 s) that satifies there is a second periastron passage within the visibility period. The observations are time critical since we want to monitor a low frequency oscillation triggered at periastron passage in a PMS spectroscopic binary. The program can only be started at Julian Dates (JD0)satisfying, 0.9914956 = (JD0-2446654.3634)/13.609453-INT(JD0-2446654.3634)/13.609453 and requires a subsequent visit a JD1s 1.9914956 = (JD1-2446654.3634)/13.609453-INT(JD0-2446654.3634)/13.609453 Visibility windows when this is possible are indicated in the description using the Visit Planner tool. UNRESOLVED STAR FORMATION 12 false true 0.0 0.0 false false false SUPPORTED STAR EMISSION LINE STAR INTERACTING BINARY PRE-MAIN SEQUENCE STAR T TAURI STAR This object was generated by the targetselector and retrieved from the SIMBAD database. The object is bright enough to be included in the GSC with entry number 07371-00870 (entry according SIMBAD Database). Proper motions are retrieved also from SIMBAD, they are based in the New Hipparcos reduction (van Leeuwen 2007, A&A,474,653). They are ICRS thus I've assigned epoch 2000. Also HD 152404 J2000 J2000 COS/FUV Spectroscopic No No G130M 1309 COS/NUV Spectroscopic No No G285M 2695 COS/FUV Spectroscopic No No G160M 1600 COS/FUV Spectroscopic No No G130M 1309 COS/NUV Spectroscopic No No G285M 2695 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 1374531492803 The scheduling data was generated by CASM 21.2. CASM was run in Phase II mode. Zero phase HJD, "T (J:D:) = 46 654.3634 " from Alencar et al. 2003, A&A 409, 1037. TO this value, I have added 2,440,000. Please double check. kf - 07.02.13 (Tic-Visit :proposal-id 13372 :visit-id "01" :proposal-version -1 :trans-version "20130502" :date "22-Jul-2013 16:18:12.0" :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 1705024 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13372 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13372 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2954 :al-overhead-at-end 0 :internal-dur-at-end 2163 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 2163 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "01" :orbit-number 3 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) false 3 0 1374531734870 Timing link suitability includes constraints ([03 After 02 by 13.6 to 13.6 days]) The scheduling data was generated by CASM 21.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 13372 :visit-id "02" :proposal-version -1 :trans-version "20130502" :date "22-Jul-2013 16:22:14.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 2331200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13372 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13372 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2954 :al-overhead-at-end 0 :internal-dur-at-end 2163 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "02" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 2163 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "02" :orbit-number 3 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 2163 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "02" :orbit-number 4 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) false 4 0 1374531791146 Timing link suitability includes constraints ([03 After 02 by 13.6 to 13.6 days]) The scheduling data was generated by CASM 21.2. CASM was run in Phase II mode. Reviewed by kf - June 20 2013. BOT Checked for COS and STIS, 06/20/13. Only warnings are where target star has been misidentified in the GSC2 catalog. (Tic-Visit :proposal-id 13372 :visit-id "03" :proposal-version -1 :trans-version "20130502" :date "22-Jul-2013 16:23:09.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 7 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 1957472 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13372 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13372 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2937 :al-overhead-at-end 0 :internal-dur-at-end 67 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "03" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 48 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "03" :orbit-number 3 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 48 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "03" :orbit-number 4 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 48 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "03" :orbit-number 5 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 48 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "03" :orbit-number 6 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 48 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13372 :visit-id "03" :orbit-number 7 :pcs-time 222 :si-vis-utilization 3065 :al-overhead-at-end 0 :internal-dur-at-end 385 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3287 :pcs-gap 0 ) false 7 0 This is the first exposure of the monitoring (see proposal description)