The measurement errors in the Swift-UVOT and XMM-OM

Abstract

The probability of photon measurement in some photon counting instrumentation, such as the Optical Monitor on the XMM-Newton satellite, and the UVOT on the Swift satellite, does not follow a Poisson distribution due to the detector characteristics, but a Binomial distribution. For a single-pixel approximation, an expression was derived for the incident countrate as a function of the measured count rate by Fordham, Moorhead and Galbraith (2000). We show that the measured countrate error is binomial, and extend their formalism to derive the error in the incident count rate. The error on the incident count rate at large count rates is larger than the Poisson-error of the incident count rate.

4 pages, 2 postscript figures, submitted to MNRAS

References in corpus (2)

• The Swift Ultra-Violet/Optical Telescope
• The XMM-Newton Optical/UV Monitor Telescope

Cited by in corpus (24)

• SOUSA: the Swift Optical/Ultraviolet Supernova Archive
• Paper II: Calibration of the Swift ultraviolet/optical telescope
• The First Swift Ultra-Violet/Optical Telescope GRB Afterglow Catalog
• The XMM-Newton serendipitous ultraviolet source survey catalogue
• Global Star Formation Rates and Dust Emission Over the Galaxy Interaction Sequence
• The Evolving Activity of the Dynamically Young Comet C/2009 P1 (Garradd)
• The Swift-UVOT ultraviolet and visible grism calibration
• Calibration and performance of the photon-counting detectors for the Ultraviolet Imaging Telescopes (UVIT) of the Astrosat observatory
• Swift UVOT near-UV transit observations of WASP-121 b
• Revealing the dust attenuation properties on resolved scales in NGC628 with SWIFT UVOT data
• The use and calibration of read-out streaks to increase the dynamic range of the Swift Ultraviolet/Optical Telescope
• The Long-Lived UV "Plateau" of SN 2012aw
• Variations in the dip properties of the low-mass X-ray binary XB 1254-69 observed with XMM-Newton and INTEGRAL
• The Rapidly Flaring Afterglow of the Very Bright and Energetic GRB 070125
• Swift UV/Optical Telescope Imaging of Star Forming Regions in M81 and Holmberg IX
• A multiwavelength study of the Magellanic-type galaxy NGC 4449 - I. Modelling the spectral energy distribution, the ionization structure and the star formation history
• Investigating the In-Flight Performance of the UVIT Payload on ASTROSAT
• A Large Catalog of Homogeneous Ultra-Violet/Optical GRB Afterglows: Temporal and Spectral Evolution
• The XMM Deep Survey in the CDF-S VII. UV catalogue of the Optical Monitor observations
• An optical-ultraviolet flare with absolute AB magnitude of -39.4 detected in GRB 220101A
• Faint NUV/FUV Standards from Swift/UVOT, GALEX and SDSS Photometry
• A study of gamma-ray burst afterglows as they first come into view of the Swift Ultraviolet and Optical Telescope
• The calibration of read-out-streak photometry in the XMM-Newton Optical Monitor and the construction of a bright-source catalogue
• Decontaminating Swift UVOT Grism Observations of Transient Sources