Callisto low freq obs of sun
jan22
Intro
Downloading fits files
idl routines
Daily movies
Table of movies
History:
rfi
measurements
all measurements
Outstanding issues to
deal with
e-callisto
international network page:
Intro: (top)
The Callisto receiver at AO takes data between 10 to 85
Mhz. It is a swept lo spectrometer. 200 freq channels are recorded
every .25 seconds.
Current recording runs from 10:30 to 21:30 (utc) hours. At the end
of the day, the data is uploaded to the e-Callisto site.
The site generates fits files by day. For a given day
- fits files are generated holding 15 minutes of data.
- a image of 200 channels by 3600 time samples.
- A separate file is generated for polA and polB
- eg: polA: Arecibo-Observatory_20211201_103000_01.fit
- polB: Arecibo-Observatory_20211201_103000_02.fit
- 220125 - callisto off, moved system from 12meter to staging
area
- 220126 - callisto in staging area. skip
data since lots of testing going on.
- 220128 - polA went bad, cable problem. fixed
220129 later in the day
- 220216 - fits file pol names were 01,02 .. now 63,62
(lcp,rcp). the software now assumes that
- polA= 01,63(lcp)
- polB= 02,62(lcp)
Downloading the fits files to AO
The fits files are downloaded to AO using a bash
script:
- The bash scripts are currently located in
/share/megs/phil/x101/callisto/
- getcallistofiles.sc - this will download 1 days worth
of data
- getrange.sc
- downloads a range of days (it call getcallistofiles.sc for
each date)
- The downloaded fits files are located in:
- /share/phildat/callisto/yymmdd
- I'm currently downloading the files manually so it may be a
few days behind. Eventually I'll put it in a crontab .
Idl routines to access fits files
I've written some idl routines to access the
Callisto fits files:
- ecalinpday.pro - This will input a days worth of fits files
into an idl struct ecalI
- ecalimgday.pro - generate images for all of the 15 min
sets of data in an ecalI struct
- This routine is used to generate the movies below. It may
not be that useful for general use.
To use the idl Callisto routines
- idl
- @phil
- @ecalinit
- nsets=ecalinpday(yymmdd,ecalI)
- explain,ecalinpday will give some documentation on
the routine.
- ecalimgday not yet documented
Daily movies
Daily movies are available for the spectra.
Making a daily movie:
- Each frame of the movie is freq vs time for 15 minutes (2 fits
file.. pola and polB)
- top image: polA, bottom image polB
- warning.. i've used the same time offsets for polA
and B. this may be off by a second or 2.
- Scaling an image.
- Bandpass correction:
- Each freq channel is divided by its median value for the
15 minutes.
- The image is then scaled to +/- 5 sigma (where sigma
is computed using a robust estimator).
- the images are B/W instead of color.
- The x axis is time with the tickmarks at
hh:mm:ss UTC.
- Each frame of a movie is a jpeg file stored in
/share/megs/phil/x101/callisto/movie/yymmdd/
To look at a movie use mpv
- setup your web browser to use mpv for .avi files
- It's handy to generate a config file for mpv so it will
continue looping on the movie rather than quitting at the
end
- in your home directory:
- edit .mplayer
- put:
loop="0"
[gnome-mplayer]
msglevel=all=5
- Some keys that control mpv
- [ slow down the movie .. to run continuously you need
to slow it down to about .05
- ] speed up the movie;.
- space bar stop movie.. hit again to continue
- . single step forward
- , singel step backwars
The table below holds the
.avi movies
processing : x101/callisto/xxx
Notes:
- 220127: 14:45:45 UTC
- 220129: 13:37 (2) ,13:57 (2),15:54 ?(4),17:54 (3), 18:07
2(STRONG),
- 220130: 16:47 (3),17:36 *(4),18:06(3) STRONG,18:31,19:19,19:38
(>3),20:11:59 (>3),
- 220131: 13:26,13:36,14:01,14:12,14:17 (3),15:07,15:14,15:24
(2),15:32,15:49 (3),16:00 (>3),16:25 (3),16:38
(2),16:59(>3),17:13,17:24,17:30,17:48,18:13,18:15,20:18,20:34
- 220201:12:58:50(2),13:56:50,14:19:50,16:07(4),16:30:30,17:06:58,17:40:58,18:45:59
(>6)
strong,19:13:59(<3)strong+,19:14:49(>4),19:31:+(llightning?),20:46:00(>2).
- 220920 - ripples in bandpass corrected around 16:00 utc.luis
and mano found antenna tilted. Probably from hurricane
fiona.they releveled it.
- 230121-22 : callisto offline for 41Mhz radar test.
All measurements
- 220123:
5 second comb seen in data when callisto was at the 12meter
site.
- 220125: moved from 12meter site to staging area.
- 220126:
measure the callisto antenna ( rfi when the trailer door is open
and closed.
- 220127:
2.4 MHz ripple seen across the band for about 1 hour.
- 220131:
total power jump (13%) seen in polA and polB that lasted for
about 1 hour.
- 220202: 63
sec pulses,ripples, polB dropouts
Outstanding issues to deal with
- Pol B dropouts
- last for less that 1 .25 sec spectra
- dropout is across the entire freq band
- they do not occur in polA
- more info:
- 2.4 Mhz ripples that turn on.
- turn on fast (within 0 sample)
- first sample at turn on has large oscillation over part of
the band. it goes down on the next sample
- The lower level ripple occurs across the entire band.
- it can turn off and then turn back on.
- more info:
- 63.1 second periodic pulses around 27.5Mhz
- there is a 2 second power decrease followed by a 2 second
increase
- this change is only around the 27.5 mhz peak.
- The decrease does not extend across the entire band (so it
is not out of band compression).
- more info:
- total power jump of 13% that lasted for one hour
- it occurred in polA and B
- the jump was across the entire band
- more info