Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/~palfa/observing.notes/obslog.20050808.txt Дата изменения: Mon Aug 8 08:38:11 2005 Дата индексирования: Sun Apr 10 23:51:33 2016 Кодировка: Поисковые слова: южная атлантическая аномалия

Hi All,

Here is a brief observing report for 20050801 - 20050808. I have also
posted this report on the palfa web page under the logfiles
link. Ramach, Paulo, and I were here for almost all the run, while
Dunc and Maura were here for the first part. For novice observers, the
HOWTO documentation and instruction list (on the web page) is very
helpful, so be sure to get a copy of that if you need it when you
come.

Froney


MON 20050801 - lots of 12 sec broadband RFI. investigation showed FAA
activity was the cause.


TUE 20050802 - 12 sec RFI mostly gone. along with the survey obs, took
single timing obs of new pulsars (267 sec each, with ALFA):

J1901+06 (not detected)
J1904+07
J1905+08 (detected but below quicklook threshold; had 7.6 snr)
J1928+1746
J1937+20 (not detected)
J2009+28 (not detected)
J2009+33
J2010+32
J2011+33 (not detected)
J2018+34


WED 20050803 - not too much RFI. several other problems, however.

first problem: while swapping out full wapp disks in middle of run,
disk firewire41 on wapp4 crashed, causing failed blocks (why? who
knows). this prevented quick reboot or fix of wapp4. this was not the
disk we had been writing to this session, but it prevented daq with
wapp4 while we waited for disk check and reboot (wapp4 was offline for
rest of the night). some significant amount of data from a previous
run (jul05) lost on this disk. note that swapping disks in the middle
of the run also prevents quicklook processing from checking candidates
from the ongoing run. recommend always swapping wapp disks before run
starts with plenty of time to spare.

second problem: cannot re-detect some recently discovered new pulsars
(see list above). why? serious? repeat of survey pointing in which
J2009+28 didn't detect J2009+28 in any beam when it should
have. investigation planned with L-wide for comparison.


THU 20050804 - significant time spent on diagnostics with L-wide and
ALFA. looked at several known bright pulsars to gauge
sensitivity. L-band had much clearer detection in 1 min obs than ALFA
1 min obs (ALFA barely visible, may not even count as a detection). if
ALFA sensitivity is greatly reduced, this may account for the 5
non-detections yesterday. re-observed J2009+28 and J2011+33 (not
detected yesterday) with 4.5 min ALFA pointings to see if signal comes
through this time. these turned out to be non-detections again. some
survey pointings observed.


FRI 20050805 - tsys measurements being made in afternoon for all 7
ALFA beams. tsys for all beams is normal. observing went well, with
little RFI. several diagnostic obs taken of known psrs to check
throughput and parallatic correction. survey pointings for the rest of
the night. diagnostic pulsars detected, parallactic angle rotation is
ok. previous non-detections probably due to RFI.


SAT 20050806 - changed full wapp disks prior to observing. had some
trouble finding unfilled disks on site. recommend trying to get larger
supply on hand if possible for future runs. a catalog on the web page
showing which disks are ok to re-use would also be good. note that two
disks (in wapp3, wapp4) are AO disks (with AO labels). wapp4 problem
at start of observing. this is the same drive (but different disk) as
two days ago. arun fixed problem quickly. survey pointings all night.


SUN 20050807 - survey pointings. no major problems.


The status of the survey (number of pointings observed) from the
output of the catalog update program on 20050808 is appended below:

PALFA survey statistics:

3994 survey pointings have been observed in all survey_IDs
3705 of these are independent pointing_IDs

1720/1935 independent pointing_IDs/total observations from survey_ID PRECURSOR%
1547/1603 independent pointing_IDs/total observations from survey_ID Gal_center%
438/456 independent pointing_IDs/total observations from survey_ID Gal_anticenter%