HALOTIMELG - HaloSat Time Log

Overview

This table records the start and stop times of the uninterrupted observation intervals obtained by the three detectors on board of HaloSat and provides access to the HaloSat observations containing these intervals.

HaloSat is the first astrophysics-focused CubeSat funded by NASA's Astrophysics Division (PI P. Kaaret, University of Iowa). HaloSat is designed to map soft X-ray oxygen line emissions across the sky in order to constrain the mass and spatial distribution of hot gas in the Milky Way.

HaloSat was launched from the NASA Wallops Flight Facility and delivered to the International Space Station on May 21, 2018. HaloSat was deployed into orbit on July 13, 2018 and collected science data from October 15, 2018, until September 29, 2020. HaloSat reentered Earth's atmosphere on January 4, 2021.

To trace the Galactic halo, HaloSat is equipped with a non-focusing instrument, comprised of three independent silicon drift detectors (SDD14, SDD38, SDD54) operating in the energy range of 0.4 - 7.0 keV with a field of view of 10 deg in diameter and an energy resolution of 84.8 +/- 2.7 eV at 677 eV and 137.4 +/- 0.9 eV at 5895 eV.

The HaloSat data are divided by specific positions in the sky and labeled with a number, the sequence number. Each sequence number contains all data for a specific sky position collected during the HaloSat operations therefore each observation contains time intervals that may be apart day, week or months. This database table instead has in each record the start and stop times of one uninterrupted time interval of good data for a specific detector. This table therefore enables searches of the HaloSat data for a specific time event detected by different obsevatories.

Catalog Bibcode

2019ApJ...884..162K

References

HaloSat: A CubeSat to Study the Hot Galactic Halo,
   Kaaret, P.,  Zajczyk A.,  LaRocca, D. M.,  Ringuette, R.,  Bluem, J.,
   Fuelberth, W., Gulick, H., Jahoda, K., Johnson, T. E., Kirchner, D. L.,
   Koutroumpa, D., Kuntz, K. D., McCurdy, R., Miles, D. M., Robison, W. T.,
   Silich, E. M., 2019, ApJ 884 162

Provenance

The contents of this database table are generated at the HEASARC using information from the data files. The table was created in April 2023.

Parameters

ObsID
The unique number to identify an observation/sequence. This is a 6-digit number where the first 4-digit are the field number and the last 2-digit are the observation number of that field.

Name
This is the designation of the pointed target. The nomenclature for the HaloSat fields is "HaloSat JHHMM+DDMM".

RA
Right Ascension of the pointing position.

Dec
Declination of the pointing position.

LII
Galactic Longitude of the pointing position. This parameter has been added by the HEASARC and is calculated from the J2000 pointing position.

BII
Galactic Latitude of the pointing position. This parameter has been added by the HEASARC and is calculated from the J2000 pointing position.

Obs_Type
The type of observation/object. Possible values and their respective meanings: SCIENCE for a normal observation either specific objects or the HaloSat fields, CALIBRATION for a calibration observations, SWCX for observations of the magnetospheric Solar Charge Exchange emission, HALO for observations of the galactic halo, EARTH for observations on dark earth.

Processing_Date
This parameter records the date when the data were last processed.

Time_MET
The start time of the interval provided as Mission Elapsed Time in seconds. (Mission Elapsed Time is the number of seconds since the reference time of 2000-01-01 00:00:00 UTC.)

End_Time_MET
The stop time of the interval provided as Mission Elapsed Time in seconds. (Mission Elapsed Time is the number of seconds since the reference time of 2000-01-01 00:00:00 UTC.)

Time
The start time of the interval in UTC.

End_Time
The stop time of the interval in UTC.

Exposure
The total exposure of the time interval in seconds.

Det_ID
The detector identification part of the HaloSat instrument. The possible values are 14, 38, 54.

Interval_Number
The number of the interval within this table.

Contact Person

Questions regarding the HALOTIMELG database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Tuesday, 25-Apr-2023 16:40:14 EDT