... This calibration approach is recommended when dealing with high frequency data from the old ATCA correlator, especially at 3mm wavelengths. ... The approach described here exploits the dual frequency bands that were available with the old correlator. ... Rather the current approach assumes that you have a single Miriad dataset containing bandpass calibrator, phase calibrator, flux density calibrator and program source. ... MFCAL . ... Input multi-source, dual-band dataset. select=source(1921-293) . ...

... The absolute photometric accuracy of FOC observations depends on several factors. ... The remaining errors most likely arise from: 1) errors in the published fluxes or variations in fluxes of the spectrophotometric stars used to calibrate the absolute DQE, 2) errors in the assumed PSFs, 3) errors in the assumed filter transmission curves, 4) format dependence effects, 5) temporal variability in the FOC detectors, and 6) the spectrum of the source. ... Errors in the assumed filter transmission curves...

... Archives . ... They find yearly modulation in their detected scintillation rate that matches what you would expect if the Earth were rushing through Galactic Dark Matter as it goes around the Sun. ... Significant! ... Certainly, at 8-sigma, it is easy to accept that there is modulation. ... Astronomers in general are extremely suspicious of any yearly modulations, as we have learnt from hard experience that it is an extremely common source of systematic error. ... Chandra Blog . ...

... We will consider the rms, (K), for observations with a receiver of system temperature, T , frequency resolution, per polarization, and total integration time per observing cycle, . ... For ``in-band'' frequency switching, the line under investigation is always in the observing band. ... Position Switching or ``Out-of-Band'' Frequency Switching: Here the line is only observed for one half of the time, with noise being present all of the time. ...

The success of any ALMA phase-calibration strategy, which incorporates phase transfer, depends on a good understanding of how the atmospheric path delay changes with frequency (e.g. Holdaway Pardo 2001). ... We find the wet dispersive path delay becomes a significant fraction ( 5 per cent) of the non-dispersive delay for the high-frequency ALMA bands ( 160 GHz, Bands 5 to 10). ... The full text of the memo is available here . ... Dispersive path delay . 2009 Emily Curtis ...

EPIC-pn Burst Mode X-ray loading and rate-dependent CTI calibration Jan-Uwe Ness ESAC 09 April 2015 XRL / RDCTI corrections in burst mode JU Ness ESAC , April 9 2015 Energy offsets caused by X-ray loading In 2010, significant effects from X-ray loading ( XRL ) were discovered in the timing mode and burst ... Thus the values of a0, a1, a2 control the rate dependent correction and are determined empirically. ...

... Paradoxically, signal detection is concerned with fitting models to supposedly random series similarly to mathematical proofs by reductio ad absurdum of the antithesis. ... The quality of the fit is evaluated using a function S of the series , , and . ... A random variable S is characterized by its probability distribution function. ... The special realization of a random series which consists of independent variables of common (gaussian) distribution is called (gaussian) white noise. ...

... HIGH-SPEED ULTRACAM COLORIMETRY OF THE SUBDWARF B STAR SDSS J171722.08+58055.8 C. Aerts 1 2 3 4 5 1,2 C.S. Jeffery3 V.S. Dhillon4 T.R. Marsh5 and P. Groot 2 Institute of Astronomy, University ... The data was obtained during 2 consecutive nights in 2004 August using the three-channel photometer ultracam attached to the 4.2m William Herschel Telescope. ... In this poster, we present ULTRACAM multicolour photometry of the sdB star SDSS J171722.08+58055.8 (hereafter abbreviated as SDSS 1717). ...

... Astro Space Center, Profsojuznaya 84/32, GSP-7, 117997, Moscow, Russia . ... The algorithm allows to work easily with the first and the second derivatives of a visibility function phases and amplitudes. This approach is important for high orbiting Space VLBI data processing. ... where is a measurements of the visibility function and is an approximating function. ... If is a 2-D complex function (a model), the bi-orthogonal approximation is known in VLBI as a self-calibration algorithm. ...

... Science . ... Science Users Information > Data Handling and Products > Data Reduction FAQ > Why do my flux-calibrated data not agree with independent photometric measurements? ... Observing with ESO Telescopes . ... ESO-MIDAS . ... Science Data Products Forum . ... ESO Data . ... With respect to the faction of flux contained within the slit one should keep in mind that the flux standard stars are observed with a 5'' wide slit, while science data are typically observed with slit widths of 0.8'' to 1'...

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