OGLE-IV Microlensing Optical Depth and Mean Timescales — Galactic bulge
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5 26 34.1 -71 25 04.2
5h 26m 34.1s, -71d 25m 04.2s
5 27 -71 25.2
5h 27m, -71d 25.2m
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- tau — Optical depth (10-6)
- Gamma — Event rate (10-6 yr-1)
- Sigma18 — Star surface density in the range 14 < I < 18 (per arcmin2)
- Sigma21 — Star surface density in the range 14 < I < 21 (per arcmin2)
- N18 — Number of stars in the range 14 < I < 18 on a single CCD detector
- N21 — Number of stars in the range 14 < I < 21
- tE — Mean timescale t_E (days)
- 10^logtE — Timescale corresponding to mean log t_E (days)
- Nevents — Number of events (used in the mean timescale calculations)
RA Dec l b tau Gamma Sigma18 Sigma21 N18 N21 tE 10^logtE Nevents Subfield
[deg] [deg] [10^-6] [10^-6/yr] [stars / arcmin^2] [stars in ccd] [days] [days] OGLE-IV
Citations, DSS & IRAS images acknowledgment
- [OGLE-IV] microlensing optical dephts and mean timescales from Mróz et al. (2019) can be dowloaded from: http://www.astrouw.edu.pl/ogle/ogle4/microlensing_maps.
- [wikisky.org] We thank sky-map.org and wikisky.org Team for combining DSS2, H alpha, IRAS, RASS and GALEX images and making them available for the astronomical comunity.
- Original data sources as described by SkyView.
- [IRAS Sky Survey] by NASA IPAC/Jet Propulsion Laboratory, see Infrared Astronomical Satellite (IRAS) Explanatory Supplement for more information.
- [2nd Digitized Sky Survey] The UK Schmidt Telescope was operated by the Royal Observatory Edinburgh, with funding from the UK Science and Engineering Research Council (later the UK Particle Physics and Astronomy Research Council), until 1988 June, and thereafter by the Anglo-Australian Observatory. The blue plates of the southern Sky Atlas and its Equatorial Extension (together known as the SERC-J), as well as the Equatorial Red (ER), and the Second Epoch [red] Survey (SES) were all taken with the UK Schmidt.
- All data are subject to the copyright given in the copyright summary. Copyright information specific to individual plates is provided in the downloaded FITS headers.
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