English
Related papers

Related papers: The completeness and reliability of threshold and …

200 papers

In this work we address the problem of simultaneous multi-frequency detection of extragalactic point sources in maps of the Cosmic Microwave Background. We apply a new linear filtering technique, the so called `matched matrix filters', that…

Astrophysics · Physics 2009-11-13 D. Herranz , M. Lopez-Caniego , J. L. Sanz , J. Gonzalez-Nuevo

An accurate calibration of the source redshift distribution $p(z)$ is a key aspect in the analysis of cosmic shear data. This, one way or another, requires the use of spectroscopic or high-quality photometric samples. However, the…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-25 Carlos García-García , David Alonso , Pedro G. Ferreira , Boryana Hadzhiyska , Andrina Nicola , Carles Sánchez , Anže Slosar

We present an analysis of 152,355 radio sources identified in the second data release of the LOFAR Two Metre Sky Survey (LoTSS-DR2) with Sloan Digital Sky Survey (SDSS) spectroscopic redshifts in the range 0.00 < z < 0.57. Using Monte Carlo…

This article considers the detection of point sources in two dimensional astronomical images. The detection scheme we propose is based on peak statistics. We discuss the example of the detection of far galaxies in Cosmic Microwave…

Astrophysics · Physics 2009-11-10 M. Lopez-Caniego , D. Herranz , J. L. Sanz , R. B. Barreiro

Obtaining accurate photometric redshift estimations is an important aspect of cosmology, remaining a prerequisite of many analyses. In creating novel methods to produce redshift estimations, there has been a shift towards using machine…

Instrumentation and Methods for Astrophysics · Physics 2021-07-07 Ben Henghes , Connor Pettitt , Jeyan Thiyagalingam , Tony Hey , Ofer Lahav

The first Euclid Quick Data Release (Q1) provides extensive imaging and spectroscopic data for hundreds of millions of photometric objects across several deep fields. Accurate classifications and photometric redshifts (photo-z) for these…

We present maps, source lists, and number counts from the largest, unbiassed, extragalactic sub-mm survey so far undertaken with the SCUBA camera on the JCMT. Our maps cover 260 sq. arcmin, to a noise level S(850)=2.5 mJy/beam. We have…

Spectral retrieval techniques are currently our best tool to interpret the observed exoplanet atmospheric data. Said techniques retrieve the optimal atmospheric components and parameters by identifying the best fit to an observed…

Earth and Planetary Astrophysics · Physics 2020-10-21 Kai Hou Yip , Ingo P. Waldmann , Angelos Tsiaras , Giovanna Tinetti

SDSS-V will obtain 100,000s of medium-resolution, optical spectra of M dwarfs with the BOSS instrument. M dwarfs have complex atmospheres, and their spectra contain many wide and dense, overlapping molecular features, so determining…

We follow up on a report by Vacca et al. (2018) of 28 candidate large-scale diffuse synchrotron sources in an 8{\deg}$\times$8{\deg} area of the sky (centred at RA 5h0m0s Dec 5{\deg}48'0''). These sources were originally observed at 1.4 GHz…

Astrophysics of Galaxies · Physics 2022-05-27 Torrance Hodgson , Melanie Johnston-Hollitt , Benajmin McKinley , Tessa Vernstrom , Valentina Vacca

This paper extends the method introduced in Rivi et al. (2016b) to measure galaxy ellipticities in the visibility domain for radio weak lensing surveys. In that paper we focused on the development and testing of the method for the simple…

Instrumentation and Methods for Astrophysics · Physics 2018-04-16 Marzia Rivi , Lance Miller

Wide-angle photometric surveys of previously uncharted sky areas or wavelength regimes will always bring in unexpected sources whose existence and properties cannot be easily predicted from earlier observations: novelties or even anomalies.…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 A. Solarz , M. Bilicki , M. Gromadzki , A. Pollo , A. Durkalec , M. Wypych

The scope of this paper is to compare the catalog extraction performances obtained using the new combination of SExtractor with PSFEx, against the more traditional and diffuse application of DAOPHOT with ALLSTAR; therefore, the paper may…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 M. Annunziatella , A. Mercurio , M. Brescia , S. Cavuoti , G. Longo

We demonstrate two new approaches that have been developed to aid the production of future hard X-ray catalogs, and specifically to reduce the reliance on human intervention during the detection of faint excesses in maps that also contain…

High Energy Astrophysical Phenomena · Physics 2022-01-19 V. A. Lepingwell , A. J. Bird , S. R. Gunn

The completeness of source detection is critical for analyzing the photometric and spatial properties of the population of interest observed by astronomical imaging. We present a software package $\mathtt{ComEst}$, which calculates the…

Instrumentation and Methods for Astrophysics · Physics 2016-05-24 I-Non Chiu , Shantanu Desai , Jiayi Liu

One of the biggest problems faced by current and next-generation astronomical surveys is trying to produce large numbers of accurate cross identifications across a range of wavelength regimes with varying data quality and positional…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Isaac G. Roseboom , Seb Oliver , David Parkinson , Mattia Vaccari

The neutral hydrogen 21cm line is potentially a very powerful probe of the observable universe, and a number of on-going experiments are trying to detect it at cosmological distances. However, the presence of strong foreground radiations…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-14 Qizhi Huang , Fengquan Wu , Xuelei Chen

Skymaps measured with imaging atmospheric Cherenkov telescopes (IACTs) represent the real source distribution convolved with the point spread function of the observing instrument. Current IACTs have an angular resolution in the order of…

Instrumentation and Methods for Astrophysics · Physics 2015-08-26 Susanne Raab , Ira Jung-Richardt

Estimating the true background in an astronomical image is fundamental to detecting faint sources. In a typical low-photon count astronomical image, such as in the far and near-ultraviolet wavelength range, conventional methods relying on…

Instrumentation and Methods for Astrophysics · Physics 2024-11-27 Pushpak Pandey , Kanak Saha
‹ Prev 1 3 4 5 6 7 10 Next ›