.
Sergei Trushkin
Oleg Verkhodanov
Vladimir ChernenkovRadio Astronomical Telescope Academy Nauk (science) of Russia is one of the two big telescope of Special Astrophysical Observatory. BTA and RATAN-600 are largest optical and radio telescopes in Russia.
RATAN has seen 'first light' from source PKS 0521-36 12 July 1974 . Since more 50000 observations were caried out in continuum. Main advantage of the telescope is multi-frequiency (1 - 31 cm wavelength) and high bright temperature sensitivity.
Proposals for observational time we ask to send
to KTBT .
In the end of 1985 a new conical mirror and feed-cabine N6 was firstly used. That feed-cabine aloows to collect radio emission from whole circle, but range of source declinations limited in this regime the zone of zenith distance z=±6o (or Dec: 38-49o ).
| Azimuth | Hmax | Directions |
| 0o | 2o16'52" | in North |
| 90o | 2o07'00" | in East |
| 180o | 3o19'30" | in South |
| 270o | 2o39'00" | in West |
In MS DOS efemerides of sources could be calculate in program EFRAT , created in SpbITA. In database of EFRAT there are two files of parameters from 1976 to 1990 fd7690 and file jd9000 from 1990 to 2000. Two editable files efrat.ini and obser.dat allow to change location of the observatory and time zone. Ephemerides of the Sun, Moon, planets and Galiley satellites of Jupiter also as stars and radio sources could calculate from EFRAT. In Linux the programs of efemerides epoch . or task preparation of observation could be used.
In two figures the correction values UT1-UTC1 are given for period 1979 - 1996.
These corrections are smaller one second. Be careful in two dates: 31.12 - 1.01 and 30.06 - 01.07. Thus for determined azimuth
It should be noted, that in North sector railways have systematic
error in limits of 10-15 mm, thus "correct" position of carriage changes
likely.
But as usualy observer uses the same position
of carriage in sets of observations. So some years position of the horn
of 7.6 cm radiometer, '1058 mm' was correct for all range of elevations.
In figure plot of changing
of moments of source culminations with fixed position of horn,
recalculated on value of carriage, in dependence on the focal distance.
At least, for addition of records, received in different epoch, this records could carry to same epoch or to take into account changing of nutationin same period.
Program jdate [dd/mm/yy] or [jd] outputs Julian day or gives current date from Julian day, (plus day of weak and deltaUT1 in 1980-1996 with accuracy of ±0.02s) .
The programs stime (DOS) and stm calculate mean sideral time on any date (usage: stime [hh] [mm] [ss] [dd/mm/yy] ). This program takes into account passage to summer time.
Remember: in summer time correction to Greenwich time is 4 hours, for winter it is 3 hours. From 1996 this transfer became to do in last sunday of October, as in most of European counties.
Here the plot of nutation in Right ascention are shown in 1979-2001. It could be used for estimate of changing of nutation.
Refraction was involved in account of horizon coordinates as in table:
| Z | H | Refraction |
| 0o | 90o | 0 |
| 5 | 85 | 0'06" |
| ... | ... | ... |
| 84 | 6 | 10'00" |
| 85 | 5 | 11 42 |
| 86 | 4 | 14 00 |
| 87 | 3 | 17 18 |
| 88 | 2 | 22 28 |
| 89 | 1 | 30 30 |
| 90 | 0 | 38 42 |
This dependence could be roughly fitted by formula
Plot of radio refraction near RATAN-600 and its approximation of by 5-power polynome in refra (DOS).
Number of antenna elements in dependence on elevation of source: Second column gives horizon size of antenna, from formula
| H | N el. | d (m) | 1.38/d |
| 0o | 164 | 310 | -- |
| 10 | 166 | 312 | 9.1" (11") |
| 20 | 172 | 326 | - |
| 30 | 178 | 336 | - |
| 40 | 190 | 355 | - |
| 50 | 206 | 380 | 7.5" |
| 55 | 224 | 407 | - |
| 57 | 225 | 408 | 6.94" = one |
| 60 | 235 | 422 | sector |
| 65 | 256 | 461 | - |
| 70 | 280 | 478 | - |
Calculated beam of RATAN North sector antenna at 7.6 cm (H=51o).
Horizon HPBW (in Azimuth) is equal 60", and vertical one - 15'.
Base is equal 10 % of maximum value.
1976 to 1980 program carra80
1980 to 1992 program carra89
1993 to 15.03 1994 program carra93
1994 to 04.11 1996 program carra94
1996 to now program cavrra96
(by S.Trushkin)
Current and last year carriage of feed-cabine N1
Velosity of moving source image in focal line defined by formula, coincident with direct measurements:
21.23*cos(delta) North V = --------------- mm/s 1 + cos(H) South +flat mirror = 10.537*cos(delta) mm/s Geometric optics gives V = 15*cos(delta)*(r0=288470mm)/(1+cos(h))*sin(1")= =20.92*cos(delta)/( 1+cos(h) ) mm/s
|---------------------------------------------------------------------| h=90o flat h=43o50' h=0 | h>60o | h<60o | | | | | | | | | | | Fcalc 20 40 60 80 100 120 | 140 m | C--------|--------|--------|--------|--------|--------|---|----|------| S | | | | | upper c u l m i n a t |i o n | lower cul.| | | | | 43o50' dec: 75o 90o 46o |---------------------------------------------------------------------|Again formula for elevation with South sector.
| Geodesic signs | distance |
| 1 | 20014 |
| 2 | 40000 |
| 3 | 60022 |
| 4 | 80011 |
| 5 | 100011 |
| 6 | 120014 |
| 7 | 139996 |
Distance between imaginary focus and index of feed-cabine N1 (S. Golosova)
15.09.82 4884 mm
03.11.89 4869 mm
19.01.95 4862 mm
05.03.97 48?? mm
For N2 : 4926 mm
Plot of calculated focus Fcalc via elevation, as output by program focus.
Fcalc = (1-F){Rmax - 445.0(1/cos(h/2) -1) }, where
Rmax = 288470 mm;
Rmin = 287530 mm;
F = (1 - K cosh)/(1 + cosh);
K = sqrt(1 - (Rmin/Rmax)2).
For elevation 5o 1 mm of focus is equal 33" in elevation
For elevation 10o 1 mm of focus is equal 15"
For elevation 20o 1 mm of focus is equal 7"
For elevation 44o 1 mm of focus is equal 3"
For elevation 75o 1 mm of focus is equal 1"
For elevation 95o 1 mm of focus is equal 0.5"
Plots elevation of source h and hour angle t from current declination for antenna azimuths: 0, 30, 60 and 90o.
Calculation of beam and transverse aberration using algorithms by A.N. Korzhavin, rewiting in C by O. Verkhodanov and S. Trushkin. Thus any beam for real observations could be calculated.
There are version for LINUX
aberr , gs and be.
and for MS DOS aber and gst.
Plot of transverse aberration in dependance from shift distance along the carriage of feed cabine for several North sector elevation.
Plot of longitudinal aberration in dependance from shift distance along the railways of feed cabine for several North sector elevation (red - elevation 17o, yellow - elevation 77o, green - elevation 87o).
Import of files could use for remote preparation and correction of observing task-packet.
With utility prit obssatr file obssatr.p would be cteated, available for viewing. Then this files will send to user e-mail address.
Example of record of source PKS 1830-21 from a such file obsbur.p . ----------------------------------------------------------------------------- Number 3(o) File r6906p1830-21 Feed-cabine 1 Source 1830-210 Observer Bursov Date 06 09 96 Azimuth 0d00m0.00s Elevation 25d09m23.639s Horn_WL in Focus 2.70 Elevation_ef 25d09m23.640s Horn w RA 1950 18h30m41.010s Carriage 940.00 Dec1950 -21d05m32.000s Variant/Type a/d RA_date 18h33m29.090s Discret sec 0.10 Dec_date -21d03m11.457s Focus mm 147985.594 Nutation in RA 0.211s Start location 940.00 Siderial time 18h33m28.879s Velocity mm/sec 0.000 Local UTC 20h42m54.855s V(car)/V(src) 0.00 Start time 18h30m58.88s Time before RA m 2.500 Stop time 18h35m28.88s Time after RA m 2.000 ----------------------------------------------------------------------------- Channel Wave_cm Stocks Regime Clv_K Gain Tau Compress W_shift E_shift sec 2 2.70 I BS 1.35 + 5 0.00 1 0.00 -9.23 4 7.60 I SH 0.41 + 4 0.00 1 11.35 13.70 5 13.00 I SH 2.00 - 4 0.00 1 -40.39 -40.39 9 31.00 I SH 1.90 - 5 0.00 1 66.25 66.25 3 3.90 I BS 1.00 + 3 0.00 1 -14.62 -29.81 8 1.38 I BS 1.70 + 5 0.00 1 -4.71 -80.96 -----------------------------------------------------------------------------Program rr loads current packets, sent by each observer.
Program vis or xvisn are used for visualization of observations . Example of visualization of chanals 2, 3, 4, 5 and 9 with calculations of dispersion and without new time synkhronization:
In focus of cariage horns could arrange automatically from packet rr in the begining of task. The remote compensation of radiometers levels are included in the management:
Recorded files load down in archive at server (ns.ratan.sao.ru) /PUB/archive/ref1/. These multi-frequency FLEX-files named by format rYMDDaHHMM-DD, where
r - sign of records in continuum
Y - last figure of Year
M - mouth (in 16-mal system 123456789ABC)
DD - day
a/p- 'ante meridiem' or 'past meridiem' of the record. These signs follow the possible twice observations in day.
HH - source name consists of hours and minutes of RA (here B1950)
MM minutes if RA
- - sign of declination
DD - degrees in declination
p - a flag of files from data recording system of based on signal processor four-channal output of 31 cm-radiometer (pulsar.ratan.sao.ru).
These FLEX-files could be transformed in f-files by program
fl2f .
For example: by fl2f r* -dos -c comp
files for data-proccessing in MS DOS with compression in text-file comp.
In special files /users/obs/lib/chan/chanst main parameters of radiometers and parameters of registration: channels, temperature steps of noise calibration signals, arrangement of carriage, regimes and so on. Observer can create new type of observations with defined special perameters.
Transformations equatorial and galactic cordinates could be made by program epoch in Linux and fad in MS DOS.
If observer wants data-reducting with f-files in MS DOS or (dosemu in Linux) he could use program prat.
Usage:
prat filename or prat and use menu.
prat *? (wild cards use for list of files in current directiry)
prat file1 file2 file3 ... (view of n < 10 files)
prat @textfile import of text files, including colomn of float numbers.
( by T.Sokolova & S.Trushkin)
List of f-files working programs
current data-reduction of RATAN f-files include more than 80 different
programs, created by O. Verkhodanov in Linux.
His interactive program fgr
works under X-windows and has detailed manual of users.
Usage fgr file1 file2 ... [flags]
For viewing of f-files heads dff filenames could be used.
(S.Pavlov, V.Kononov)
Now with fixing of surface of main mirror elements of North sector Accuracy of the surface is better 0.2 mm.
In 1996 September new AC-adjustment of North sector.
Search of "8-points" shows value -4 point for angle.
| Wavelength | Frequency | 1sigma ( K) tau=1sec | Band (MHz) | Tsys |
| 1.38 | 21.7 | 0.015 | 1400 | 200 |
| 2.70 | 11.2 | 0.004 | 1000 | 140 |
| 3.90 | 7.7 | 0.006 | 700 | 140 |
| 7.6 | 3.95 | 0.0025 | 500 | 40 |
| 13.0 | 2.3 | 0.025 | 250 | 60 |
| 31.1 | 0.985 | 0.025 | 100 | 100 |
Radiometer at 31 cm was equiped by output to signal processor and 4 filter channal with band 30 MHz in 1996 March. (P.A. Freedman) This processor placed on PC pulsar.ratan.sao.ru and remove the impulse interference in each channals "on-line". High rate (100-1000 Hz) of data-recording allows to use this equipment for pulsar observations, as shown in probe observation of PRS 0950+08 and PSR 1133+16. The 8-channals back-end of 13 cm-radiometer is prepared and will be arrange in 1997. This system is very effective for removing of impulse or stationar interferences.
New data-recording system include regime of "sliding", allowed to follow of source during 100-150 second.
On server cats.sao.ru database CATS - supporting system
of astrophysical catalogs, see CATS preprint .
It includes procedures of selection and matching from radio or
mixed catalogs. There are the self-sufficient descriptions of every
main catalogs:
NVSS, FIRST, TEXAS, MASTER LIST, MIT-GREEN BANK, 6C, 7C, MCG-VV, PMN, NAIC...,
more 150 catalogs in CATS (O.Verkhodanov, S.Trushkin, V.Chernenkov)
Two version Kuehr et al. (1979) about spectral data of 1842 sources
and its short version Kuehr et al. (1981) about 518 sources
and PKSCAT90 are could be
use for obtaining flux data at RATAN continuum radiometers.
CGI-Program in CATS could plot "on a fly" GIF-figure of a spectrum of a source from catalogs of Kuehr at al (1979, 1981), PKSCAT90, Supernova remnants and any radio source, searched for in radio catalogs.
Here the spectrum of calibrator source 3C286 = 1328+30.
CATS database contains catalog of point IRAS sources (~250000), catalogs faint sources (450000 and |b| >10o). Dr D. Leisovitz presents kindly to N.V. Bystrova atlas of IRAS, on 8 CDs, where the FITS-maps ( size 12.5o*12.5o) are at all four bands of IRAS of whole sky. CATS authors consider to add them in the database.
Sample of sources from
VLA-list (812) of calibrator sources, brighter 2 Jy at 20 cm
and all point 3CR-sources
from this list could be useful for coordinate or focus adjustment of
antenna.
J.W.M. Baars, R.Genzel, I.I. Pauliny-Toth and A. Witzel 'The absolute Spectrum of Cas A; An accurate flux density scale and a set of Secondary Calibrators', Asrton. Astrophys., 61, 99-106, 1977.
In this paper there was established, that spectra of Cas A has accuracy 2%. Between 0.3 and 30 GHz S= 2723(Jy)*freq.-0.77 (1980.0). Spectra of Cygnus A and Taurus A are given. Precise semi-absolute spectrum of Virgo A was determined from precise relation to Cas A and Cyg A fluxes and was approximated S=285(Jy)*freq.-0.856 (good for 0.4 - 25 GHz). This spectra was used as base for relative spectra some sources with simple spectra. They are secondary standards for common day calibrations. These data are good for frequency range 0.4 - 15 GHz and seem to have absolute accuracy near 5%.
Ir was found the dependence of decreasing of flux of Cas A:
| Name | Frequency | Spectral parameters | |||
| Source | MHz | GHz | a | b | c |
| Cas_A 1965.0 | 300 | 31 | 5.880±0.025 | -0.792±0.007 | - |
| Cas_A 1980.0 | 300 | 300 | 5.745±0.025 | -0.770±0.007 | - |
| Cyg A | 20 | 2 | 4.695±0.018 | +0.085±0.003 | -0.178±0.001 |
| Cyg A | 2000 | 31 | 7.161±0.051 | -1.244±0.014 | - |
| Tau A | 1000 | 35 | 3.915±0.031 | -0.299±0.009 | - |
| Vir A | 400 | 25 | 5.023±0.034 | -0.856±0.010 | - |
| Name | Frequency | Spectral parameters | |||
| Source | MHz | GHz | a | b | c |
| 3C48 | 405 | 15 | 2.345±0.030 | +0.071±0.001 | -0.138±0.001 |
| 3C123 | 405 | 15 | 2.921±0.025 | -0.002±0.000 | -0.124±0.001 |
| 3C147 | 405 | 15 | 1.766±0.017 | +0.447±0.006 | -0.184±0.001 |
| 3C161 | 405 | 10.7 | 1.633±0.016 | +0.498±0.008 | -0.194±0.001 |
| 3C218 | 405 | 10.7 | 4.497±0.038 | -0.910±0.011 | - |
| 3C227 | 400 | 15 | 3.460±0.055 | -0.827±0.016 | - |
| 3C249.1 | 400 | 15 | 1.230±0.027 | +0.288±0.007 | -0.176±0.003 |
| 3C286 | 405 | 15 | 1.480±0.018 | +0.292±0.006 | -0.124±0.001 |
| 3C295 | 405 | 15 | 1.485±0.013 | +0.759±0.009 | -0.255±0.001 |
| 3C348 | 400 | 10.7 | 4.963±0.045 | -1.052±0.014 | - |
| 3C353 | 405 | 10.7 | 2.944±0.031 | -0.034±0.001 | -0.109±0.001 |
| DR21 | 7000 | 31 | 1.81 ±0.05 | -0.122±0.010 | - |
| NGC7027 | 10000 | 31 | 1.32 ±0.08 | -0.127±0.012 | - |
| Source | Frequency [GHz] | ||||||
| 0.96 | 1.42 | 2.30 | 3.65 | 3.90 | 7.70 | 11.20 | |
| Cas_A1980. | 2809.6 | 2078.4 | 1433.7 | 1004.7 | 954.7 | 565.5 | 423.7 |
| Cyg_A | 2319.4 | 1563.8 | 952.8 | 536.4 | 494.0 | 211.9 | 133.0 |
| Tau_A | 1055.1 | 938.6 | 812.5 | 707.7 | 693.9 | 566.2 | 506.2 |
| Vir_A | 295.2 | 211.2 | 139.7 | 94.1 | 88.9 | 49.7 | 36.1 |
| 3C48 | 21.35 | 15.76 | 10.57 | 7.03 | 6.61 | 3.44 | 2.34 |
| 3C123 | 64.89 | 48.14 | 32.58 | 21.89 | 20.64 | 10.97 | 7.58 |
| 3C147 | 29.01 | 22.22 | 15.46 | 10.55 | 9.96 | 5.30 | 3.62 |
| 3C161 | 24.70 | 18.84 | 13.02 | 8.81 | 8.31 | 4.35 | 2.94 |
| 3C218 | 60.69 | 42.50 | 27.40 | 18.00 | 16.95 | 9.13 | 6.49 |
| 3C227 | 9.86 | 7.13 | 4.78 | 3.27 | 3.09 | 1.76 | 1.29 |
| 3C249.1 | 3.34 | 2.45 | 1.62 | 1.05 | 0.99 | 0.49 | 0.32 |
| 3C286 | 17.70 | 14.73 | 11.49 | 8.84 | 8.50 | 5.52 | 4.26 |
| 3C295 | 30.24 | 22.06 | 14.28 | 8.97 | 8.36 | 3.83 | 2.38 |
| 3C348 | 66.93 | 44.34 | 26.70 | 16.42 | 15.32 | 7.49 | 5.05 |
| 3C353 | 74.67 | 56.71 | 39.62 | 27.52 | 26.08 | 14.64 | 10.45 |
| DR21 | (5.0) | - | (12.1) | (17.3) | (17.4) | 21.67 | 20.70 |
| NGC7027 | 0.94 | - | (2.64) | (4.77) | (4.9) | (6.47) | 6.39 |
Accepted flux densities at RATAN are given in ().
This scale was used for spectral catalogs by Kuehr et al. (1979, 1981):
H.Kuhr, A. Witzel, I.I.K. Pauliny-Toth and U.Nauber
A catalogue of extragalactic radio sources having flux densities greater
than 1 Jy at 5 GHz Astron. Astrophys. S.S. 45, 367-430, 1981,
and MPIfR Preprint Nr 55, 1979.
| Source | RA(1950) | DEC(1950) | Ident. | Size | Pol % | Pos. angle |
| name | hh mm ss.sss | dd mm ss.s | '' | at 3.9 cm | at 3.9 cm (deg) | |
| 3C48 | 01 34 49.832 | +32 54 20.5 | QSO | 1.5 x 1.5 | 4. | 113 |
| 0237-23 | 02 37 52.803 | -23 22 06.2 | QSO | 2 x 2 | 5.9 | 134 |
| 3C123 | 04 33 55.2 | +29 34 14. | GAL | 23 x 5 | 1.0 | - |
| 3C138 | 05 18 16.53 | +16 35 27.0 | QSO | 0.3 x 0.3 | 11.8 | 171 |
| 3C147 | 05 38 43.507 | +49 49 42.8 | QSO | 1 x 1 | 1.4 | 0 |
| 3C161 | 06 24 43.19 | -05 51 11.8 | GAL | 3 x 3 | 2.8 | 104 |
| 3C218 | 09 15 41.5 | -11 53 06. | GAL | 47 x 15(200") | 1. | 6 |
| 3C227 | 09 45 07.8 | +07 39 09. | GAL | 200 x 50 | 4.7 | 157 |
| 3C249.1 | 11 00 25.0 | +77 15 11. | QSO | 15 x 15 | 3.0 | 158 |
| *1151-34 | 11 51 49.35 | -34 48 47.5 | QSO | 2 x 2 | 1.0 | - |
| *1245-197 | 12 45 45.218 | -19 42 57.51 | QSO | <1 x 1 | <1. | - |
| 3C286 | 13 28 49.657 | +30 45 58.6 | QSO | 1.5 x 1.5 | 11.3 | 34 |
| 3C295 | 14 09 33.5 | +52 26 13. | GAL | 5 x 1 | 1.5 | 130 |
| 3C309.1 | 14 58 56.64 | +71 52 10.8 | QSO | 1.5 x 1.5 | 2.6 | 34 |
| 3C348 | 16 48 40.1 | +05 04 28. | GAL | 170 x 25 | 7.2 | 25 |
| 3C353 | 17 17 54.6 | -00 55 55. | GAL | 210 x 60 | 6.2 | 91 |
| DR21 | 20 37 14.3 | +42 09 07. | HII | 20 x 20 | 0 | 0 |
| NGC7027 | 21 05 09.4 | 42 02 03.1 | PN | 7 x 10 | 0 | 0 |
R - radius of source, phi05 - size of beam (HPBW):
wavelengths 1.38 2.7 3.9 7.6 13 31 cm Kdisc(North) 1.20 1.10 1.07 1.02 1.01 1.0Linear polarisation mast be taken to account for estimate of Aeff:
where p - power of linear polarisation
Xa - positional angle of antenna (accepted of polarization plane)
Xs - positional angle of source
Xra - positional angle of RA-axis (for Azimith 0: Xra=270o) angle are account from North to East.
F = 1/2 if source is unpolarized, as ussually. But F could change from 1 - p/2 to 1 + p/2 , thus error of measurements without polarization data are 1/(1 ± p) in Aeff or measured flux. Compilation of polarization measurements collected in paper: Tabara et al., AASS, 1980, 39, 379 - 393. Details of such measurements are given in Aliakberov et al. (1989).
| Name | Frequency | Spectral parameters | |||
| Source | MHz | GHz | a | b | c |
| 3C48 | 1408 | 23.8 | 2.465 | -0.004 | -0.1251 |
| 3C123 | 1408 | 23.8 | 2.525 | +0.246 | -0.1638 |
| 3C147 | 1408 | 23.8 | 2.806 | -0.140 | -0.1031 |
| 3C161 | 1408 | 10.55 | 1.250 | +0.726 | -0.2286 |
| 3C218 | 1408 | 10.55 | 4.729 | -1.025 | +0.0130 |
| 3C227 | 1408 | 4.75 | 6.757 | -2.801 | +0.2969 |
| 3C249.1 | 1408 | 4.75 | 2.537 | -0.565 | -0.0404 |
| Vir A | 1408 | 10.55 | 4.484 | -0.603 | -0.0280 |
| 3C286 | 1408 | 43.2 | 0.956 | +0.584 | -0.1644 |
| 3C295 | 1408 | 43.2 | 1.490 | +0.756 | -0.2545 |
| 3C309.1 | 1408 | 32.0 | 2.617 | -0.437 | -0.0373 |
| 3C348 | 1408 | 10.55 | 3.852 | -0.361 | -0.1053 |
| 3C353 | 1408 | 10.55 | 3.148 | -0.157 | -0.0911 |
| Cyg A | 4750 | 10.55 | 8.360 | -1.565 | - |
| NGC7027 | 10550 | 43.2 | 1.322 | -0.134 | - |
| Source | Frequency [GHz] | |||||||
| 0.96 | 1.42 | 2.30 | 3.65 | 3.90 | 7.70 | 11.20 | 21.20 | |
| 3C48 | 21.90 | 16.19 | 10.91 | 7.30 | 6.88 | 3.63 | 2.50 | 1.24 |
| 3C123 | 63.36 | 47.08 | 31.68 | 21.02 | 19.77 | 10.16 | 6.85 | 3.25 |
| 3C147 | 29.62 | 21.89 | 14.80 | 9.98 | 9.41 | 5.07 | 3.54 | 1.82 |
| 3C161 | 24.10 | 18.49 | 12.80 | 8.62 | 8.11 | 4.16 | 2.76 | 1.26 ? |
| 3C218 | 61.35 | 42.37 | 26.92 | 17.48 | 16.44 | 8.74 | 6.19 | 3.38 ? |
| 3C227 | 11.07 | 7.55 | 4.97 | 3.52 | 3.37 | - | - | - |
| 3C249.1 | 3.11 | 2.26 | 1.52 | 1.03 | 0.97 | - | - | - |
| Vir_A | 273.31 | 201.81 | 38.18 | 95.64 | 90.68 | 52.18 | 38.30 | 22.0 ? |
| 3C286 | 17.20 | 14.56 | 11.52 | 8.92 | 8.57 | 5.53 | 4.22 | 2.49 |
| 3C295 | 30.28 | 22.09 | 14.30 | 8.98 | 8.37 | 3.84 | 2.39 | 0.96 |
| 3C309.1 | 9.59 | 7.39 | 5.33 | 3.86 | 3.69 | 2.27 | 1.72 | 1.05 |
| 3C348 | 69.00 | 46.52 | 28.08 | 16.97 | 15.77 | 7.22 | 4.61 | 2.02 ? |
| 3C353 | 74.05 | 55.95 | 38.96 | 27.08 | 25.67 | 14.51 | 10.44 | 5.68 ? |
| Cyg_A | - | - | - | - | 49.50 | 89.51 | 105.43 | 37.4 ? |
| NGC7027 | - | - | - | - | - | 6.33 | 6.02 | >5.51 |
Log S = A + B * Log v + C * (Log v)2 + D * (Log v)3where S is the flux density in Jy and v is the frequency in MHz. These expressions are valid between 300 MHz and 50 GHz. Table1.
| Name | Spectral parameters | |||
| Source | A | B | C | D |
| 3C48 | 1.16801 | +1.07526 | -0.42254 | +0.02699 |
| 3C138 | 1.97498 | -0.23918 | +0.01333 | -0.01389 |
| 3C147 | 0.05702 | +2.09340 | -0.70760 | +0.05477 |
| 3C286 | 0.50344 | +1.05026 | -0.31666 | +0.01602 |
| 3C295 | 1.28872 | +0.94172 | -0.31113 | +0.00569 |
Below are listed the RATIOS between the true and Baars et
al. value for 3C48, 3C147 and 3C286 at the various frequency bands
from 1983 to 1995. Multiply the Baars et al. value by this ratio to
obtain the correct flux density.
Contact R. Perley or G. Taylor if you need more information.
In bands: 20cm=L 6cm=C 3.7cm= X 2cm=U 0.7cm=Q.
| Source | Band | 20cm | 6cm | 3.7cm | 2cm | epoch |
| P | L | C | X | U | ||
| 3C48 | - | 1.004 | 1.039 | - | - | 1983.5 |
| 3C48 | - | 1.018 | 1.047 | - | 1.11 | 1985.5 |
| 3C48 | 0.95 | 1.02 | 1.04 | 1.06 | 1.10 | 1987 |
| 3C48 | - | 1.019 | 1.043 | 1.049 | 1.076 | 1989.9 |
| 3C48 | 0.948 | 1.017 | 1.023 | 1.034 | 1.034 | 1995.2 |
| 3C147 | - | 0.974 | 0.957 | - | - | 1983.5 |
| 3C147 | - | 0.970 | 0.948 | - | 0.99 | 1985.5 |
| 3C147 | 1.00 | 0.97 | 0.95 | 0.97 | 1.01 | 1987 |
| 3C147 | - | 0.975 | 0.951 | 0.949 | 0.993 | 1989.9 |
| 3C147 | 0.990 | 0.983 | 0.974 | 0.999 | 1.046 | 1995.2 |
| 3C286 | - | 0.995 | 1.010 | - | - | 1983.5 |
| 3C286 | - | 0.993 | 1.002 | - | 0.99 | 1985.5 |
| 3C286 | 0.95 | 1.00 | 1.01 | 1.01 | 1.02 | 1987 |
| 3C286 | - | 0.999 | 1.005 | 0.995 | 0.991 | 1989.9 |
| 3C286 | 0.971 | 0.999 | 1.008 | 1.006 | 0.988 | 1995.2 |
New values of flux densities for RATAN radiometers, calculated from Table 1.
| Source | Frequency [GHz] | |||||||
| 0.96 | 1.42 | 2.30 | 3.65 | 3.90 | 7.70 | 11.20 | 21.20 | |
| 3C48 | 21.506 | 16.004 | 10.787 | 7.186 | 6.765 | 3.540 | 2.431 | 1.219 |
| 3C147 | 28.806 | 21.891 | 15.084 | 10.252 | 9.680 | 5.249 | 3.698 | 1.972 |
| 3C286 | 17.545 | 14.769 | 11.591 | 8.924 | 8.576 | 5.529 | 4.244 | 2.567 |
| 3C295 | 30.265 | 22.073 | 14.274 | 8.962 | 8.351 | 3.830 | 2.390 | 0.968 |
| 3C138 | 10.276 | 8.287 | 6.221 | 4.615 | 4.413 | 2.700 | 2.008 | 1.137 |
| Source | Frequency [GHz] | ||||||||
| 0.96 | 2.30 | 3.65 | 3.90 | 7.70 | 11.20 | 14.40 | 22.3 | ||
| 0023-26 | - | 10.70 | 5.99 | 5.28 | 4.41 | 2.38 | - | 1.3 | - |
| 0237-23 | - | 6.75 | 5.05 | 4.21 | 3.87 | 2.73 | (2.25) | 1.93 | - |
| 1830-21 | - | 14.00 | 10.90 | 9.90 | 9.99 | 8.55 | - | 6.43 | 5.2 |
| 0159-11 | 3C57 | 3.77 | 1.76 | 1.50 | 1.48 | 0.95 | - | - | - |
| 0624-05 | 3C161 | 24.20 | 12.50 | 8.90 | 8.07 | 4.22 | (2.76) | 2.13 | 1.88 |
| 0003-00 | 3C2 | 5.06 | 2.27 | 1.79 | 1.76 | 1.02 | - | - | - |
| 2314+03 | 3C459 | 7.82 | 6.68 | 9.74 | 1.54 | 0.84 | - | - | - |
| 2128+04 | - | 5.30 | 3.17 | 2.28 | 2.34 | 1.29 | - | 1.09 | - |
| 0518+16 | 3C138 | 11.25 | 6.66 | 4.71 | 4.15 | 3.00 | - | 1.62 | - |
| 0428+20 | - | 3.50 | 3.47 | 2.69 | 2.83 | 2.16 | - | 0.97 | - |
| 0433+29 | 3C123 | 63.70 | 30.90 | 23.50 | 21.05 | 11.51 | (6.85) | 6.47 | 3.12 |
| 0134+32 | 3C48 | 21.50 | 10.91 | 7.30 | 6.88 | 3.63 | (2.50) | 1.9 | (1.20 |
| 2105+42 | N7027 | 0.94 | 2.64 | 4.77 | 4.90 | 6.47 | (6.50) | 6.9 | 6.0 |
| 2037+42 | DR21 | 5.0 | 12.10 | 17.30 | 17.40 | 21.50 | (20.50) | 18.7 | 21.2 |
This is experimental formula for effective area and Integral coefficient, receiving from obvsevations of calibrators in 1992 Febrary with North sector (7 groups). (by Trushkin)
Aeff( 2.7cm) = 3.072*H + 360.5 m2 ( 4o - 80o )
Aeff( 7.6cm) = 4.653*H + 574.4 m2 (20o - 80o )
Aeff(31.1cm) = 1202 -7.17931H +0.441936H2 -0.005004H3 m2
K_Jy/Ks( 2.7cm) = 1.485 + 0.0735H - 0.000727H2 or
K_Jy/Ks( 2.7cm) = (3.07 - 0.0035H)*cos(Dec)
K_Jy/Ks( 7.6cm) = 0.623 - 0.0101H - 0.0001181H2 or
K_Jy/Ks( 7.6cm) = (0.885 - 0.0009H)*cos(Dec)
K_Jy/Ks(31.1cm) = 0.0844 - 0.00102H or
K_Jy/Ks(31.1cm) = 0.2062 - 0.000641F
| Wavelength | Aeff(m2) | 1 Jansky = | 100 mK = |
| 1.4 | 400 | 0.144 K | 690 mJy |
| 2.7 | 900 | 0.326 | 307 |
| 3.9 | 900 | 0.326 | 307 |
| 7.6 | 1000 | 0.362 | 276 |
| 13.0 | 900 | 0.326 | 307 |
| 31.0 | 1200 | 0.435 | 230 |
We recommend use calibrator curves in depend of focus distance, but of elevation. Then in full range of declination such curves could be fitted by 1-st or 2-nd power polynomes. This conclusion bases on observations, but calculations.
Next steep spectrum sources could be use as secondary calibrators 0552+398, 1345+125 at long (>8cm) wavelengths. 1245-197, 1328+254, 1511+238, 2352+495 at every wavelengths. (by S. Trushkin).
| Source | RA1950 +- | DEC1950 +- | Ident. | Mag. | Z |
| 0742+10 | 074248.47±.01 | +101832.6 ± .1 | EF | - | - |
| 1151-34 | 115149.35±.04 | -344847.5 ± .5 | QSO | 17.5 | 0.258 |
| 1245-19 | 124545.22±.01 | -194257.6 ± .1 | QSO | 20.5 | - |
| 1328+25 | 132815.92±.01 | +252437.6 ± .1 | QSO | 17.7 | 1.055 |
| 1345+12 | 134506.19±.01 | +123220.0 ± .3 | GAL | 17.0 | 0.122 |
| 1442+101 | 144250.48±.01 | +101111.9 ± .2 | QSO | 18.4 | 3.53 |
| 1511+23 | 151128.2 ± - | +234944. ± | EF | - | .41 |
| 2352+49 | 235237.79±.01 | +493326.8 ± .1 | GAL | 19.0 | 0.237 |
| Frequency | 0742+10 | 1151-34 | 1245-19 | 1328+25 | 1345+12 | 1442+10 | 1511+23 | 2352+49 |
| 960 | 3.40 | 7.44 | 6.78 | 8.90 | 6.01 | 2.50 | 1.96 | 2.87 |
| 1420 | 4.00 | 6.09 | 5.66 | 7.07 | 5.28 | 2.27 | 1.51 | 2.72 |
| 2300 | 4.25 | 4.59 | 4.29 | 5.24 | 4.29 | 1.88 | 1.12 | 2.35 |
| 3650 | 4.01 | 3.40 | 3.14 | 3.88 | 3.38 | 1.47 | 0.86 | 1.91 |
| 3900 | 3.95 | 3.25 | 2.99 | 3.71 | 3.26 | 1.41 | 0.82 | 1.84 |
| 4850 | 3.69 | 2.79 | - | 3.20 | 2.87 | 1.23 | 0.73 | 1.63 |
| 7700 | 3.02 | 1.98 | 1.76 | 2.33 | 2.16 | 0.90 | 0.58 | 1.21 |
| 11200 | 2.44 | 1.49 | 1.28 | 1.79 | - | 0.67 | 0.48 | 0.92 |
| 21700 | 1.53 | 0.87 | - | 1.11 | - | - | - | 0.54 |
We recommend to see database of 26-m radio telescope of Michigan University, which includes weekly measurement of flux densities of ~200 bright radio sources at three frequencies: 4.8, 8.0 and 14.5 GHz, among of these sources there are slowly variable point sources. database UMRAO .
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