TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2626 SUBJECT: XRF040701: First-Epoch Chandra Observations DATE: 04/07/12 17:09:09 GMT FROM: Derek Fox at CIT D.B. Fox (Caltech) reports on behalf of a larger collaboration: "We have observed the HETE localization region for XRF040701 (Barraud et al., GCN 2620) with the Chandra X-ray Observatory + ACIS for 22.3 ksec beginning at 07:35 UT on July 9, 2004. The observation aimpoint and dither pattern provide coverage of the full 8'-radius error circle, with some decrease in exposure over the chip gaps of the ACIS-I array. A comprehensive "wavdetect" analysis provides the following catalog of sources detected with >3-sigma confidence in or near (<15") the HETE localization region (coordinates are J2000): # Name RA Dec Flux DSS? ================================================================== 1 CXOU J204720.7-401941 20 47 20.696 -40 19 41.52 25.6 2 CXOU J204816.1-401108 20 48 16.097 -40 11 08.83 11.1 Y* 3 CXOU J204746.6-401357 20 47 46.602 -40 13 57.15 9.0 4 CXOU J204724.0-401056 20 47 23.970 -40 10 56.07 8.8 Y 5 CXOU J204719.1-401234 20 47 19.056 -40 12 34.33 8.5 6 CXOU J204805.7-401823 20 48 05.696 -40 18 23.01 8.1 7 CXOU J204751.8-401936 20 47 51.810 -40 19 36.90 8.0 8 CXOU J204706.2-401445 20 47 06.231 -40 14 45.66 7.7 9 CXOU J204805.3-401233 20 48 05.337 -40 12 33.74 6.1 10 CXOU J204736.2-401623 20 47 36.158 -40 16 23.76 6.0 Y 11 CXOU J204739.2-401748 20 47 39.249 -40 17 48.32 5.5 Y 12 CXOU J204810.0-400721 20 48 09.981 -40 07 21.19 5.4 13 CXOU J204740.3-401225 20 47 40.281 -40 12 25.99 4.5 14 CXOU J204823.3-401801 20 48 23.282 -40 18 01.06 4.3 15 CXOU J204733.1-401447 20 47 33.118 -40 14 47.48 4.1 16 CXOU J204712.3-401112 20 47 12.288 -40 11 12.49 4.1 17 CXOU J204810.1-401932 20 48 10.054 -40 19 32.71 4.1 18 CXOU J204751.4-400603 20 47 51.377 -40 06 03.64 3.9 19 CXOU J204756.5-400715 20 47 56.453 -40 07 15.01 3.9 20 CXOU J204755.7-401347 20 47 55.713 -40 13 47.56 3.8 Y 21 CXOU J204747.3-401516 20 47 47.349 -40 15 16.97 3.7 Y 22 CXOU J204734.7-401042 20 47 34.678 -40 10 42.16 3.7 23 CXOU J204809.7-401005 20 48 9.739 -40 10 05.74 3.6 ================================================================== 24 CXOU J204816.9-401146 20 48 16.866 -40 11 46.55 3.0 25 CXOU J204749.9-40 627 20 47 49.854 -40 06 27.14 2.8 Y 26 CXOU J204810.3-401256 20 48 10.259 -40 12 56.78 2.7 27 CXOU J204736.3-401426 20 47 36.341 -40 14 26.55 2.6 28 CXOU J204748.6-40 828 20 47 48.624 -40 08 28.52 2.5 29 CXOU J204717.1-40 825 20 47 17.085 -40 08 25.65 2.3 30 CXOU J204803.5-401028 20 48 03.514 -40 10 28.77 2.0 31 CXOU J204803.3-401047 20 48 03.294 -40 10 47.68 1.8 32 CXOU J204808.1-401842 20 48 08.121 -40 18 42.44 1.8 33 CXOU J204748.3-401504 20 47 48.309 -40 15 04.50 1.8 34 CXOU J204748.3-401600 20 47 48.316 -40 16 00.24 1.8 35 CXOU J204747.8-401512 20 47 47.796 -40 15 12.32 1.7 36 CXOU J204758.1-401735 20 47 58.094 -40 17 35.49 1.5 37 CXOU J204728.4-401429 20 47 28.350 -40 14 29.01 1.4 ================================================================== Source positions have been adjusted for the observation boresight correction of (0.4" E, 0.1" S), determined by reference to DSS images of the field, and are uncertain by +/- 0.5" (two-sigma). Approximate 0.3-8.0 keV fluxes are given in units of 1E-06 photons/cm^2/s, and sources with an identifiable counterpart in the DSS are indicated ("Y"). Source #2, CXOU J204816.1-401108, is unique among these ("Y*") in that it is associated with a resolved galaxy or galaxies in the DSS, perhaps reminiscent of the host galaxy of GRB031203 (Prochaska et al. 2004, astro-ph/0402085). We expect the X-ray afterglow of XRF040701 to be found in the brighter portions of the above catalog. In particular, most known X-ray afterglows would have F_X above the 3E-06 photons/cm^2/s division indicated in the table. A second observation of this region is scheduled for July 18, 2004, with processed data products expected within three days of the observation. Results of the observation and a comparison of the two epochs will be reported by GCN at that time." We acknowledge an extraordinary effort by the CXC in providing rapid processing of this challenging data-set, thereby enabling this report.