University of Hertfordshire Research Archive

        JavaScript is disabled for your browser. Some features of this site may not work without it.

        Browse

        All of UHRABy Issue DateAuthorsTitlesThis CollectionBy Issue DateAuthorsTitles

        Arkivum Files

        My Downloads
        View Item 
        • UHRA Home
        • University of Hertfordshire
        • Research publications
        • View Item
        • UHRA Home
        • University of Hertfordshire
        • Research publications
        • View Item

        An IPHAS-based search for accreting very low-mass objects using VO tools

        View/Open
        903371.pdf (PDF, 236Kb)
        Author
        Valdivielso, L.
        Martin, E.L.
        Bouy, H.
        Solano, E.
        Drew, J.E.
        Greimel, R.
        Gutierrez, R.
        Unruh, Y.C.
        Vink, J.S.
        Attention
        2299/3363
        Abstract
        Context. The main goal of this paper is to prove that accreting very low-mass stars and brown dwarfs can be identified in IPHAS, an H emission survey of the northern Milky Way. Full exploitation of the IPHAS database and a future extension of it in the southern hemisphere will be useful in identifying very low-mass accreting objects near to and far from well-known star-forming regions. Aims. We have used Virtual Observatory tools to cross-match the IPHAS catalogue with the 2MASS catalogue. We defined photometric criteria to identify H emission sources with near-infrared colours similar to those of known young very low-mass stars and brown dwarfs. 4000 candidates were identified that met our criteria over an area of 1600 square degrees. We present low-resolution optical spectra of 113 candidates. Spectral types have been derived for the 33 candidates that have spectroscopically confirmed H emission, negligible reddening and spectral class M. We have also measured H emission and investigated the NaI doublet (818.3 nm, 819.5 nm) in these 33 objects. Methods. We confirm that 33 IPHAS candidates have strong H emission indicative of disc accretion for their spectral type. Twenty-three of them have spectral class M4 or later, of which ten have classes in the range M5.5–M7.0 and could thus be very young brown dwarfs. Many objects also have a weak NaI doublet, an indication of low surface gravity. Results. IPHAS provides a very valuable database for identifying accreting very low-mass stars and brown dwarfs. Virtual Observatory tools provide an efficient method for identifying these objects over large areas of the sky. Based on our success rate of 23 H emission objects with spectral type in the range M4–M7 out of 113 candidates with spectroscopic follow-up, we estimate that there could be hundreds of such objects in the full IPHAS survey.
        Publication date
        2009
        Published in
        Astronomy and Astrophysics
        Published version
        https://doi.org/10.1051/0004-6361/200810256
        Other links
        http://hdl.handle.net/2299/3363
        Metadata
        Show full item record
        Keep in touch

        © 2019 University of Hertfordshire

        I want to...

        • Apply for a course
        • Download a Prospectus
        • Find a job at the University
        • Make a complaint
        • Contact the Press Office

        Go to...

        • Accommodation booking
        • Your student record
        • Bayfordbury
        • KASPAR
        • UH Arts

        The small print

        • Terms of use
        • Privacy and cookies
        • Criminal Finances Act 2017
        • Modern Slavery Act 2015
        • Sitemap

        Find/Contact us

        • T: +44 (0)1707 284000
        • E: ask@herts.ac.uk
        • Where to find us
        • Parking
        • hr
        • qaa
        • stonewall
        • AMBA
        • ECU Race Charter
        • disability confident
        • AthenaSwan