10343( 2) - 08/26/04 13:50 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 10343 Version: 2 Check-in Date: 26-Aug-2004 17:49:12 1.Proposal Title: X-ray from misaligned FRI jets: IC/CMB emission from a fast spine? ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle 4. Parallel Pointing Tolerance GO 13 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Dr. Rita M. Sambruna George Mason University CoI: Dr. Fabrizio Tavecchio Osservatorio Astronomico di Brera, Milano N CoI: Dr. Mario Gliozzi George Mason University N CoI: Mr. Davide Donato George Mason University N CoI: Dr. Chi Cheung Massachusetts Institute of Technology N CoI: Dr. Laura Maraschi Osservatorio Astronomico di Brera, Milano N ------------------------------------------------------------------------------------ 6. Abstract There is evidence that FRI jets have a fast "spine", consisting of relativistically moving plasma, and a slow "wall", decelerated by entrainement of ambient gas. This opens the interesting possibility that inverse Compton scattering of the CMB photons (IC/CMB) off the relativistic electrons could contribute to the high-energy emission from the fast spine. This strongly beamed radiation is visibile only in closely aligned FRI jets, i.e., acccording to unification schemes, in BL Lac objects. Thus, we propose to observe 2 radio-selected BL Lacs with prominent radio jets to search for IC/CMB X-ray emission and confirm unification models. This study will impact models for the origin of the FRI/II division. ------------------------------------------------------------------------------------ 10343( 2) - 08/26/04 13:50 - [ 2] Observations Description ------------------------ We aim at one observation of the target to constrain the optical flux of any possible jet related emission. The selected instrument is the ACS because of its larger observing efficiency, with the WFC camera and the filter F814W (Broad I). The exposure times were calculated using the exposure time calculator (ETC), assuming $\alpha_{ro}=0.8$ and fluxes predicted by our models. We calculated the exposures necessary to obtain a signal-to-noise ratio per pixel of 3. This gives total exposures of 1 orbit for 2007+777. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- We set preferred range of ORIENT to keep diffraction spikes away from the position of the known radio jet. ------------------------------------------------------------------------------------ 10343( 2) - 08/26/04 13:50 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 2007+777 GALAXY, BL LAC RA=20H05M30.9000S +/- 0.1", J2000 V = 16.5+/-1.0 DEC=+77D52'43.00" +/- 0.1" Coordinate Source: HST_IMAGE 10343( 2) - 08/26/04 13:50 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.17 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 47.23 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 10343( 2) - 08/26/04 13:50 - [ 5] Visit: 01 Visit Priority: Visit Requirements: ORIENT 15.0D TO 59.0 D; ORIENT 105.0D TO 149.0 D; ORIENT 195.0D TO 239.0 D; ORIENT 285.0D TO 329.0 D 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 2007+777 ACS/WFC ACCUM WFC1 F814W CR-SPLIT=NO 1 921 S PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Visit Id| Exp Id |Primary |Secondary |Iteration |CR-SPLIT |Orbit Num |Duration | |Pattern Pos |Pattern Pos |Num |Num | | ------------------------------------------------------------------------------------------------------------------------------------ 01 1 1 none none none 1 921.0 01 1 2 none none none 1 921.0 01 1 3 none none none 1 921.0 10343( 2) - 08/26/04 13:50 - [ 6] Summary Form for Proposal 10343 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WFC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 15.0D TO 59.0 D; ORIENT 105.0D TO 149.0 D; ORIENT 195.0D TO 239.0 D; ORIENT 285.0D TO 329.0 D PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names 2007+777 ------------------------------------------------------------------------------------------------------------------------------------