0 Assigned ID: 644 ----- Attempting Submission 1 (Fri Apr 10 18:25:56 GMT 2015) ----- HST Phase I Proposal 644 (psrj0108.apt) successfully submitted. Receipt: # 644-1 0 ----- Attempting Submission 1 (Wed Jul 22 14:30:41 GMT 2015) ----- ----- Attempting Submission 2 (Fri Jan 29 09:01:25 GMT 2016) ----- The program has been resubmitted owing to a bug in the APT software, which affected amendments of target coordinates in the APT xml file. The old pulsar PSR J0108-1431, a key target to understand the long-term evolution of neutron stars The multi-wavelength study of >100 Myr old radio-pulsars holds the key to understanding the long-term evolution of neutron stars, including the advanced stages of the surface cooling history, and possible variations in the magnetosphere properties. Near-UV observations of neutron stars are particularly important for such studies because they offer the chance to explore both thermal and non-thermal emission processes. The first aim of this proposal is to obtain a robust detection of the candidate optical counterpart (U=26.4) to the 166 Myr old radio pulsar PSR J0108-1431, discovered by us with the VLT, through WFC3/UVIS imaging in the U and B bands. The detection of a point source at the pulsar radio position, computed from its VLBI radio coordinates and proper motion, with U and B-band fluxes compatible with those of the candidate counterpart, will firmly secure our proposed identification. The second aim is to obtain the first measurement of the pulsar flux in the optical-UV with both the WFC3/UVIS and the ACS/SBC. This will enable us to determine the slope of the Rayleigh-Jeans continuum, only hinted in the VLT data, affected by large errors, and measure the temperature of the bulk of the neutron star surface, too cold to be detected in the X-rays where only hot polar caps have been detected with Chandra and XMM-Newton. The measured temperature will provide the crucial information to constrain neutron star cooling curves for ages>100 Myr, where theoretical predictions are highly uncertain, and from them verify different models of the neutron star interior. This proposal has two goals. The first one is to confirm the identification of the old pulsar PSR J0108-1431 through absolute HST astrometry and comparison with the very accurate pulsar position obtained from radio measurements. The second goal is to study the optical/UV spectrum of this pulsar to characterise the slope of its, likely, thermal spectrum and derive its brightness temperature, thanks to accurate distance to the pulsar, also obtained from radio observations. In this way, we will be able to compare the inferred temperature with cooling models and investigate whether the neutron star surface temperature has been raised by re-heating processes in the interior, as observed in other pulsars. This will provide us with important information on the neutron star interior and composition. To fulfill our goals, we need observations performed in the optical and in the near-UV. Therefore, we plan to observe our target in the optical with the WFC3/UVIS In three filters (225W, 336W, 438W) and in the near-UV with the ACS/SBC in one filter (F140LP). The WFC3 and ACS observations should be performed in two diferent visits. For the WFC3 observations we require two orbits for each of the selected filter, for a total of six orbits (visit 1). For the ACS observations we require two orbits (visit 2). We do not have any time constraints for our observations and we have no specific sequence for the visits and exposure execution. In all cases, observations will be performed in ACCUM mode. There is no bright star close to our target so that we do not require any particular roll angle constraint to avoid that the saturation spikes overlap the target position HOT STARS 12 false true false false 0.0 0.0 SUPPORTED STAR PULSAR J2000 J2000 U = 26.4 +/-0.3 STAR PULSAR J2000 J2000 U = 26.4 +/-0.3 WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F438W ACS/SBC Imaging No No F140LP POS-TARG DITHER 0.173 LINE 0.112 false false 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 1 false The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. /metone/mignani/Proposals/HST/CYCLE23/PHASE2/OP-cache/14249_CHECKED_OFF-v02.xml 1453112895000 72.38702447325801 (Tic-Visit :proposal-id 14249 :visit-id "02" :proposal-version -1 :trans-version "20150609" :date "22-Jan-2016 10:30:47.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "28" :si-bright-earth-limb-angle 20.0 :data-volume 37040 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14249 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14249 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2881 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "02" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2940 :al-overhead-at-end 0 :internal-dur-at-end 77 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) true 2 0 The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. /metone/mignani/Proposals/HST/CYCLE23/PHASE2/OP-cache/14249_CHECKED_OFF-v01.xml 1448704573000 52.98156972999291 (Tic-Visit :proposal-id 14249 :visit-id "01" :proposal-version -1 :trans-version "20150609" :date "22-Jan-2016 10:30:50.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 6 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 6930032 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14249 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14249 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2885 :al-overhead-at-end 123 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2993 :al-overhead-at-end 123 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "01" :orbit-number 3 :pcs-time 222 :si-vis-utilization 2993 :al-overhead-at-end 123 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "01" :orbit-number 4 :pcs-time 222 :si-vis-utilization 2993 :al-overhead-at-end 123 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "01" :orbit-number 5 :pcs-time 222 :si-vis-utilization 2990 :al-overhead-at-end 122 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "01" :orbit-number 6 :pcs-time 222 :si-vis-utilization 2990 :al-overhead-at-end 122 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) true 6 0 The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. /metone/mignani/Proposals/HST/CYCLE23/PHASE2/OP-cache/14249_CHECKED_OFF-v52.xml Copy of failed visit 02 with updated target coordinates. (Tic-Visit :proposal-id 14249 :visit-id "52" :proposal-version -1 :trans-version "20150609" :date "22-Jan-2016 10:30:51.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "28" :si-bright-earth-limb-angle 20.0 :data-volume 37040 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14249 :visit-id "52" :obset-id "52" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14249 :visit-id "52" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2881 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "52" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2940 :al-overhead-at-end 0 :internal-dur-at-end 77 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) true 2 0 The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. /tmp/OPVisit2709479218580076803.xml Copy of failed visit 01 with updated target coordinates. (Tic-Visit :proposal-id 14249 :visit-id "51" :proposal-version -1 :trans-version "20150609" :date "29-Jan-2016 09:59:15.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 6 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 6930032 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14249 :visit-id "51" :obset-id "51" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14249 :visit-id "51" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2882 :al-overhead-at-end 122 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "51" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2870 :al-overhead-at-end 122 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "51" :orbit-number 3 :pcs-time 222 :si-vis-utilization 2990 :al-overhead-at-end 122 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "51" :orbit-number 4 :pcs-time 222 :si-vis-utilization 2990 :al-overhead-at-end 122 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "51" :orbit-number 5 :pcs-time 222 :si-vis-utilization 2987 :al-overhead-at-end 121 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14249 :visit-id "51" :orbit-number 6 :pcs-time 222 :si-vis-utilization 2987 :al-overhead-at-end 121 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) true 6 0