LEDAS  
Leicester Database and Archive Service
 
ARNIE Index
ARNIE Help
ARNIE Tutorial
Search...
All databases
All helpfiles
Line
Footer
E-mail

LE: Help

LE - Catalog CMA Central 6 Arcmin


Overview

This database table contains results from the LE telescope for only the central 6 arc-minutes. It is the same as the CMA database in every other respect.

References

De Korte P.A.J. et al., 1981, Sp. Sci. Rev., Vol. 30, p. 495.

White N.E. and Peacock A.P. 1988, in X-ray Astronomy with
  EXOSAT, [eds. N.E. White and R. Pallivicini], Memoria S. A. It, p. 59.

Data Products

Images and lightcurves are available with this database table. They were generated using a standard, automatic analysis of the data. There is also a background lightcurve from a source-free region of the detector.

Count Rate to Flux

To convert LE count rates to fluxes, do the following:
 * log in to the `legacy.gsfc.nasa.gov` anonymous ftp area
 * go to `caldb/data/exosat/cma/cpf`
 * copy the `.rmf` file for the filter instrument combination you need
 * start XSPEC, then:

 model wabs po        (or whatever your model is)
 fakeit none
 10000                (or whatever your exposure is)
 flux 0.1 2.5
The `fakeit` and `flux` commands will give the flux and count rate for the model you have specified.

Parameters

_100_Micron_IRAS_Flux
IRAS Flux 4

_12_Micron_IRAS_Flux
IRAS Flux 1

_25_Micron_IRAS_Flux
IRAS Flux 2

_60_Micron_IRAS_Flux
IRAS Flux 3

Al_Count_Rate
Counting rate from the Al/P filter, if available from an observation of the same source made within one day. `AL count rate error` gives the error on the Al/P counting rate.

Al_Count_Rate_Error
Al/Par Count Rate Error

Background_Per_Sqpix
Background level in counts/s per square pixel.

BII
The galactic latitudes of the sources are stored under the parameter name `BII`.

Bo_Count_Rate
Counting rate from the boron filter, if available (see AL count rate). `BO count rate error` error on boron counting rate.

Bo_Count_Rate_Error
Boron Count Rate Error

BV_Color
B-V Color

Class
Browse Object Classification

Count_Rate
The `count rate` and `count rate error` are the average counting rate (per sec) over the observation and its associated one sigma uncertainty.

Count_Rate_Error
Error on count rate

Deadtime_Factor
detector deadtime correction factor

Dec
The `Dec` is that of the detected source if the sample is not TARGETS or TOTAL. It is the coordinates of the pointing position if the sample is TARGETS. For the latter sample the `count rate` equals -1.0.

Detection_Significance
The probability of the detection being due to random chance. Note, this is not scaled for the independent number of search attempts in an image.

Diamond_Filter
Set to 1 if an OBC program with a diamond filter was used. These filters electronically screened out the outer part of the image.

Error_Radius
The 90% confidence uncertainty in arc minutes for the LE1 telescope.

Expected_Variance_Ta1
Expected Variance in TA1

Expected_Variance_Ta2
Expected Variance in TA2

Exposure_Time
The `exposure` is the total on source observation time in seconds. This includes all dead time effects, interruptions in coverage etc.

File_Bglcurve
file with bg light curve

File_Image
Compresssed Image Name

File_Lcurve
file with light curve

Filter
The filter numbers are

   * 7 = 3000 (thin) lexan

   * 6 = al/p

   * 8 = boron

   * 2 = PPL

   * 3 = 4000 (thick) lexan
  

ID_Number
Source Order Number

Instrument
The LE telescope used (L1 or L2).

IPC_Count_Rate
IPC Count Rate

IPC_Count_Rate_Error
IPC Count Rate Error

Last_Update
MJD key record update

Lightcurve_Prefix
Rates buffer identifier (first letter)

LII
The galactic longitudes of the sources are stored under the parameter name `LII`.

ME_1_To_3_Count_Rate
ME count rate in 1-3keV band

ME_1_To_3_Count_Rate_Err
ME count rate error in 1-3keV band

ME_3_To_6_Count_Rate
ME count rate in 3-6 keV band

ME_3_To_6_Count_Rate_Err
ME count rate error in 3-6 keV band

ME_Count_Rate
Counting rate from the ME detector during this observation (warning this may not cover exactly the same time interval), it also covers the central field of view and so will include all sources seen by the LE. `ME count rate error` gives the error on the count rate.

ME_Count_Rate_Error
Me count rate error

Name
The name of the EXOSAT target/field. There are many serendipitous sources in the EXOSAT LE images, and in some cases the name given here will reflect the original target name and not the actual source name.

NH_21cm
21 cm NH thru the galaxy H cm**-2

Observed_Variance_Ta1
Observed Variance in TA1

Observed_Variance_Ta2
Observed Variance in TA2

Offset_Angle_Of_Detectio
Distance from xpix=15, ypix=15

Old_Dead_Time
Dead Time Correction

Old_NH_21cm
NH (10**19 cm-2) in the Galaxy

PI_Code
Pricipal Investigator Code

Point_Source_Flag
Point Source Flag

Processed_Date
MJD key buffer creation

Proposal_Type
Proposal Type (HLX etc.)

Qflag_LE
Quality flag for the LE. This is a number between 1 and 5, where 5 is excellent, and 1 means there may be a serious problem with the entry. A value of 3 means that the entry should be checked. E.g. all boron filter entries have a qflag of 3, to warn of the problem with the psf for soft sources observed with this filter.

Qflag_Me
Me Quality Flag

RA
The `RA` is that of the detected source if the sample is not TARGETS or TOTAL. It is the coordinates of the pointing position if the sample is TARGETS. For the latter sample the `count rate` equals -1.0.

Radio_5GHz_Flux
Radio Flux (mJy) at 5 GHz

Radio_Flag
Flag for Radio Emission

Redshift
Redshift or HD Number of Counterpart

Res_Of_Lc
Gives the time resolution of the associated data product light curve in seconds. The time resolution was 2**n seconds, where n was optimized such that the average number of counts per bin is 0.3.

ROSAT_ID
ROSAT Id (spare)

Sequence_Number
sequence number

Serendipity_Flag
flag for serendipitous sources

Tape_No
archive tape # where files are stored

Time
The `time` of the observation refers to the start time. This is listed as yr.day, where yr is the last two digits of the year and day is the day of the year e.g. day 300 of 1984 is 84.300. All times are stored internally as a short history file key (SHF) which is the number of seconds before or after 1 January 1980 at 00:00 hrs UT. Times are accurate to the nearest second.

UB_Color
U-B color

Vmag
V magnitude

X_Pixels
For imaging instruments the pixel coordinates of the source in the detector are given by the parameters `X pixels` and `Y pixels`.

Y_Pixels
For imaging instruments the pixel coordinates of the source in the detector are given by the parameters `X pixels` and `Y pixels`.


Contact Person

Questions regarding the LE database table can be addressed to the HEASARC User Hotline.
If you have any problems, please consult the help page or mail ledas-help@star.le.ac.uk
 
HOME
SEARCH
SERVICES INFO SOFTWARE ViZieR BLASTA DSS
ARCHIVES ASCA CHANDRA GINGA ROSAT ARNIE