From vlbiop@hia.nrc.ca Mon Jun 7 09:25:40 1999 From: VLBI Operator To: VSOG , Bill Scott - UofC Cc: Tapasi Ghosh , rf@astro.uni.torun.pl, Glen Langston - GREEN BANK GRT , VLBI Friend Account , kevin.j.miller@jpl.nasa.gov, support@dots.jpl.nasa.gov Subject: PI Letter for VS02j ========================================================================== PI INFORMATION LETTER FROM PENTICTON S2 CORRELATOR FOR EXPERIMENT VS02j ========================================================================== Dear PI: This letter is to inform you of some of the details of the correlation and analysis of your experiment 'VS02j'. Your contact person at the correlator is: Kevin Douglas Tel: (250) 493-2277 Fax: (250) 493-7767 email: Kevin.Douglas@hia.nrc.ca and is the person who correlated your experiment. You can also contact the University of Calgary Radio Astronomy Lab for assistance with data reduction and imaging using AIPS and DIFMAP. The data package that we are sending you contains this letter and the FITS data tape in the format requested in the VS02j.sum file. Additionally, there are a number of files on the University of Calgary ftp server that will be of interest to you. The .txt file is anonymous access and all other files are restricted access only. These files include: VS02j_DQA1.txt -- ASCII *summary* file of single baseline fringe search results. VS02j.dqa1 -- ASCII file of single baseline fringe search results. VS02j.ps -- postscript plot of experiment station playback times. VS02j_DQA1.ps.gz -- gzipped postscript file of plots of single baseline fringe search results. This includes plots of phase cal extracted at the correlator and available in your FITS data. VS02j.log -- log file generated by the correlator. VS02j.comments -- comments extracted from station log files. VS02j.tsys -- Tsys data extracted from station log files. This is not formatted to read into AIPS but is provided as auxillary information if Tsys files are not otherwise available. In addition, since this is Space VLBI data there may be times when delay discontinuities occur on space baselines (VSOP_SC) -- due to tracking station handovers and 'clock setting events' at individual tracking stations resulting from momentary loss of downlink lock. These will show up as glitches or delay jumps in the VSOP_SC phase cal data and in the fringe fits results. For convenience, all times across which fringe fitting should not be done are at the end of this file in a format ready to be read in by AIPS' INDXR. The tracking passes are as follows: 'GBANK_TS' 1999-116-17:36:35 --> 1999-116-22:11:59 'TDBIN_TS' 1999-116-23:15:08 --> 1999-117-00:25:19 ...and periods of downlink loss are as follows: 116-19:41:29.230 -> 116-19:41:34.220 116-22:11:21.630 -> 116-23:17:08.000 You will have approximately 3 weeks from today (Sun Jun 6 16:41:54 PDT 1999) to look at the data and request recorrelation if there is a problem. Recorrelation requests will only be *considered* if the data is bad and it can be traced to the correlator or if there is a valid scientific reason (such as a change of correlation parameters or change of source coordinates). PLEASE LOOK AT THE DATA AS SOON AS POSSIBLE SINCE YOUR FEEDBACK TO THE MISSION IS IMPORTANT. Please contact the UofC RAL as soon as you are satisfied with the data so that re-cycling of VLBI tapes can occur with your input in a timely manner. If the data is bad or not scientifically acceptable due to problems at acquisition time, you must contact the VSOG to request re-observation of the radio source. If the data is good, then in accordance with mission policy, 18 months after it is released from the correlator, it will be available to any PI on a request basis. Good luck with your data! ================================= Correlator PR/Data analyst notes: ================================= The data from GB is not vaild until 18:36 UT. The data from HH also appears to be bad from 18:00 to 18:30 UT. Only 7 transports were able to record data at GB, and as a result the data for baselines including GB are marked DATA VALID LOW. Nevertheless, we find strong fringes with the GB GRT. The only baseline without detectable fringes is VSOP*TR. Data for the TR GRT were recorded onto S2 tapes from VLBA tapes in Mitaka. The data for TR feature short (approximately 20 minute) passes with usable data, followed by gaps of around 30 minutes with no data. Though the data pass was not continuous we were successful in correlating the data and detected fringes with TR for the first time on this job. The stream statistics for AR have shown a slight positive skew that may have resulted from a DC bias. Van Vlek corrections have been made to account for the skew and AR is aware of the situation. No clock offsets were applied to the Tracking Stations. The GRT clock model offsets are as follows: AR +4.544 usec GB -26.50 usec HH +0.56 usec TR +0.70 usec Your FITS tape(s) incl: 4 FITS files, 329546880 bytes total Participating GRTS: AR, GB, HH, TR ================== POINTS OF CONTACT: ================== ---Correlator--- Operations email: vlbiop@hia.nrc.ca Operations Manager (Sean Dougherty): Sean.Dougherty@hia.nrc.ca Tel: (250) 493-2277 (~16:00 to 24:00 UT) Fax: (250) 493-7767 Web: http://www.drao.nrc.ca Anonymous ftp: ftp.drao.nrc.ca /pub/vsop Address: Attn: Space VLBI Dominion Radio Astrophysical Observatory Hertzberg Institute of Astrophysics National Research Council of Canada White Lake Road (P.O. Box 248) Penticton, B.C. Canada V2A 6K3 ---University of Calgary RAL--- Bill Scott: bill@ras.ucalgary.ca Russ Taylor: russ@ras.ucalgary.ca Tel: (403) 220-7424 Fax: (403) 289-3331 Web: http://www.ras.ucalgary.ca ftp: cougar.ras.ucalgary.ca public directories: /pub/vsop/ restricted directories: /usr/home/vsopobs/vsop/ (contact Bill Scott for restricted access permissions) Address: Attn: Bill Scott/Russ Taylor Physics and Astronomy Department University of Calgary 2500 University Dr. NW, Calgary, Alberta, Canada T2N 1N4 ---The VSOG (VSOP Science Operations Group)--- email: vsog@vsop.isas.ac.jp S2 Scheduler: Ian Avruch (avruch@halca.vsop.isas.ac.jp) Tel: +81-427-59-8346 (8am to 6pm JST) Fax: +81-427-69-8949 Web: http://www.vsop.isas.ac.jp (Web site contains schedule information, experiment status details, HALCA calibration data and data reduction info.) Address: ISAS, 3-1-1 Yoshinodai, Sagamihara Kanagawa 229, Japan ---AIPS/Data Reduction--- VSOP Data Reduction Exploder (VDR): vdr@aoc.nrao.edu -- for general help and exchange of information regarding VSOP data reduction. 'Designated AIP': daip@aoc.nrao.edu -- for reporting bugs in AIPS. ! ! Start of Formatted entries for input to AIPS' INDXR. ! These epochs are times across which fringe fitting should not be done. ! They include all tracking station handovers and clock setting events. ! SUBARRAY = 1 / 116 19:41:29.230 116 22:11:21.630 / -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- Kevin Douglas email:Kevin.Douglas@hia.nrc.ca VLBI Data Controller DRAO, Penticton BC phone:(250)493-2277 fax:(250)493-7767 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+