Databases

Currently, two databases are maintained in order to characterize the FUV dark rate.

The SQLite Database, cos_dark

This database tracks the dark counts over binned regions of the FUV detectors. The SQLite database is available on Box- contact Jo Taylor for details.

To access the database, you will need SQLite if you do not already have it. Once you have it, simply type:

sqlite3 cos_dark.db

and start exploring! For tips on SQLite queries, click here.

Interactive plots of dark counts vs. time are available in the plot_dark_vs_time.ipynb jupyter notebook.

SQLite Database Format

The format of the cos_darks SQLite database is as follows:

SQLite Darks Table

column	type	description
id	Integer	Primary key ID number
filename	String	Filename e.g. ipppssoot_corrtag_a.fits
segment	String	COS FUV segment
expstart	Float	MJD start time
exptime	Float	Exposure time [s]
hv	Integer	High Voltage
latitude	Float	Observatory latitude
longitude	Float	Observatory longitude
region	String	Region of interest on segment
region_area	String	Area of region
xcorr_min	Integer	Region starting XCORR
xcorr_max	Integer	Region ending XCORR
ycorr_min	Integer	Region staring YCORR
ycorr_max	Integer	Region ending YCORR
solar_flux	Float	Interpolated solar flux at expstart
fileloc	String	STScI disk location of file
dark_pha<x>	Integer	Total dark counts over region for PHA <x> 0 through 31

SQLite Solar Table

column	type	description
time	Float	MJD date of solar flux measurement
flux	Float	10.7cm radio flux

Solar flux values are obtained from NOAA.

The MySQL database, hstcal

The MySQL database, hstcal, is hosted on an STScI internal server. To access the hstcal database, you need MySQL version >= 8. For connection information, contact Jo Taylor.

MySQL Database Format

There is a table for each HV setting, and each table is named like darkeventshv<hvsettings>. <hvsetting> is one of the following:

• 163

• 167

• 169

• 171

• 173

• 178

• other

The format of all hstcal tables is:

MySQL Darkevents Tables

column	type	description
id	Integer	Primary key ID number
xcorr	Decimal(12,5)	XCORR location of dark event
ycorr	Decimal(12,5)	YCORR location of dark event
pha	Integer	PHA value of dark event
mjd	Decimal(12,5)	MJD time of dark event
hv	Integer	High Voltage of corresponding dark exposure
segment	String(5)	Segment of corresponding dark exposure
filename	String(30)	Filename of corresponding dark exposure
proposid	Integer	Proposal ID of corresponding dark exposure