Browsing by Author "Harvanek, M"

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    A Lyα-only active galactic nucleus from the Sloan Digital Sky Survey
    (2004) Hall, PB; Hoversten, EA; Tremonti, CA; Vanden Berk, DE; Schneider, DP; Strauss, MA; Knapp, GR; York, DG; Hutsemékers, D; Newman, PR; Brinkmann, J; Frye, B; Fukugita, M; Glazebrook, K; Harvanek, M; Heckman, TM; Ivezic, Z; Kleinman, S; Krzesinski, J; Long, DC; Neilsen, E; Niederste-Ostholt, M; Nitta, A; Schlegel, DJ; Snedden, S
    The Sloan Digital Sky Survey has discovered a z = 2.4917 radio-loud active galactic nucleus (AGN) with a luminous, variable, low-polarization UV continuum, H I two-photon emission, and a moderately broad Lyalpha line (FWHM similar or equal to 1430 km s(-1)) but without obvious metal-line emission. SDSS J113658.36+024220.1 does have associated metal-line absorption in three distinct, narrow systems spanning a velocity range of 2710 km s(-1). Despite certain spectral similarities, SDSS J1136+0242 is not a Lyman break galaxy. Instead, the Lyalpha and two-photon emission can be attributed to an extended, low-metallicity narrow-line region. The unpolarized continuum argues that we see SDSS J1136+0242 very close to the axis of any ionization cone present. We can conceive of two plausible explanations for why we see a strong UV continuum but no broad-line emission in this "face-on radio galaxy'' model for SDSS J1136+0242: the continuum could be relativistically beamed synchrotron emission that swamps the broad-line emission, or more likely, SDSS J1136+0242 could be similar to PG 1407+265, a quasar in which for some unknown reason the high-ionization emission lines are very broad, very weak, and highly blueshifted.
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    Magnetic white dwarfs from the Sloan Digital Sky Survey: The first data release
    (2003) Schmidt, GD; Harris, HC; Liebert, J; Eisenstein, DJ; Anderson, SF; Brinkmann, J; Hall, PB; Harvanek, M; Hawley, S; Kleinman, SJ; Knapp, GR; Krzesinski, J; Lamb, DQ; Long, D; Munn, JA; Neilsen, EH; Newman, PR; Nitta, A; Schlegel, DJ; Schneider, DP; Silvestri, NM; Smith, JA; Snedden, SA; Szkody, P; Berk, DV
    Beyond its goals related to the extragalactic universe, the Sloan Digital Sky Survey (SDSS) is an effective tool for identifying stellar objects with unusual spectral energy distributions. Here we report on the 53 new magnetic white dwarfs discovered during the first two years of the survey, including 38 whose data are made public in the 1500 deg(2) First Data Release. Discoveries span the magnitude range 16.3 less than or equal to g less than or equal to 20.5, and based on the recovery rate for previously known magnetic white dwarfs, the completeness of the SDSS appears to be high for reasonably hot stars with B greater than or similar to 3 MG and g greater than or similar to 15. The new objects nearly double the total number of known magnetic white dwarfs and include examples with polar field strengths B-p > 500 MG, as well as several with exotic atmospheric compositions. The improved sample statistics and uniformity indicate that the distribution of magnetic white dwarfs has a broad peak in the range similar to5-30 MG and a tail extending to nearly 10(9) G. Degenerates with polar fields B-p greater than or similar to 50 MG are consistent with being descendents of magnetic Ap/Bp main-sequence stars, but low- and moderate-field magnetic white dwarfs appear to imply another origin. Yet-undetected magnetic F-type stars with convective envelopes that destroy the ordered underlying field are attractive candidates.
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    Sloan Digital Sky Survey
    (2002) Stoughton, C; Lupton, RH; Bernardi, M; Blanton, MR; Burles, S; Castander, FJ; Connolly, AJ; Eisenstein, DJ; Frieman, JA; Hennessy, GS; Hindsley, RB; Ivezic, Z; Kent, S; Kunszt, PZ; Lee, BC; Meiksin, A; Munn, JA; Newberg, HJ; Nichol, RC; Nicinski, T; Pier, JR; Richards, GT; Richmond, MW; Schlegel, DJ; Smith, JA; Strauss, MA; SubbaRao, M; Szalay, AS; Thakar, AR; Tucker, DL; Vanden Berk, DE; Yanny, B; Adelman, JK; Anderson, JE; Anderson, SF; Annis, J; Bahcall, NA; Bakken, JA; Bartelmann, M; Bastian, S; Bauer, A; Berman, E; Böhringer, H; Boroski, WN; Bracker, S; Briegel, C; Briggs, JW; Brinkmann, J; Brunner, R; Carey, L; Carr, MA; Chen, B; Christian, D; Colestock, PL; Crocker, JH; Csabai, IN; Czarapata, PC; Dalcanton, J; Davidsen, AF; Davis, JE; Dehnen, W; Dodelson, S; Doi, M; Dombeck, T; Donahue, M; Ellman, N; Elms, BR; Evans, ML; Eyer, L; Fan, XH; Federwitz, GR; Friedman, S; Fukugita, M; Gal, R; Gillespie, B; Glazebrook, K; Gray, J; Grebel, EK; Greenawalt, B; Greene, G; Gunn, JE; de Haas, E; Haiman, Z; Haldeman, M; Hall, PB; Hamabe, M; Hansen, B; Harris, FH; Harris, H; Harvanek, M; Hawley, SL; Hayes, JJE; Heckman, TM; Helmi, A; Henden, A; Hogan, CJ; Hogg, DW; Holmgren, DJ; Holtzman, J; Huang, CH; Hull, C; Ichikawa, SI; Ichikawa, T; Johnston, DE; Kauffmann, G; Kim, RSJ; Kimball, T; Kinney, E; Klaene, M; Kleinman, SJ; Klypin, A; Knapp, GR; Korienek, J; Krolik, J; Kron, RG; Krzesinski, J; Lamb, DQ; Leger, RF; Limmongkol, S; Lindenmeyer, C; Long, DC; Loomis, C; Loveday, J; MacKinnon, B; Mannery, EJ; Mantsch, PM; Margon, B; McG'hee, P; Mckay, TA; McLean, B; Menou, K; Merelli, A; Mo, HJ; Monet, DG; Nakamura, O; Narayanan, VK; Nash, T; Neilsen, EH; Newman, PR; Nitta, A; Odenkirchen, M; Okada, N; Okamura, S; Ostriker, JP; Owen, R; Pauls, AG; Peoples, J; Peterson, RS; Petravick, D; Pope, A; Pordes, R; Postman, M; Prosapio, A; Quinn, TR; Rechenmacher, R; Rivetta, CH; Rix, HW; Rockosi, CM; Rosner, R; Ruthmansdorfer, K; Sandford, D; Schneider, DP; Scranton, R; Sekiguchi, M; Sergey, G; Sheth, R; Shimasaku, K; Smee, S; Snedden, SA; Stebbins, A; Stubbs, C; Szapudi, I; Szkody, P; Szokoly, GP; Tabachnik, S; Tsvetanov, Z; Uomoto, A; Vogeley, MS; Voges, W; Waddell, P; Walterbos, R; Wang, SI; Watanabe, M; Weinberg, DH; White, RL; White, SDM; Wilhite, B; Wolfe, D; Yasuda, N; York, DG; Zehavi, I; Zheng, W
    The Sloan Digital Sky Survey (SDSS) is an imaging and spectroscopic survey that will eventually cover approximately one-quarter of the celestial sphere and collect spectra of 10 6 galaxies, 100,000 quasars, 30,000 stars, and 30,000 serendipity targets. In 2001 June, the SDSS released to the general astronomical community its early data release, roughly 462 deg(2) of imaging data including almost 14 million detected objects and 54,008 follow-up spectra. The imaging data were collected in drift-scan mode in five bandpasses (u, g, r, i, and z); our 95% completeness limits for stars are 22.0, 22.2, 22.2, 21.3, and 20.5, respectively. The photometric calibration is reproducible to 5%, 3%, 3%, 3%, and 5%, respectively. The spectra are flux- and wavelength-calibrated, with 4096 pixels from 3800 to 9200 Angstrom at R approximate to 1800. We present the means by which these data are distributed to the astronomical community, descriptions of the hardware used to obtain the data, the software used for processing the data, the measured quantities for each observed object, and an overview of the properties of this data set.
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    The first data release of the Sloan Digital Sky Survey
    (2003) Abazajian, K; Adelman-McCarthy, JK; Agüeros, MA; Allam, SS; Anderson, SF; Annis, J; Bahcall, NA; Baldry, IK; Bastian, S; Berlind, A; Bernardi, M; Blanton, MR; Blythe, N; Bochanski, JJ; Boroski, WN; Brewington, H; Briggs, JW; Brinkmann, J; Brunner, RJ; Budavári, T; Carey, LN; Carr, MA; Castander, FJ; Chiu, K; Collinge, MJ; Connolly, AJ; Covey, KR; Csabai, I; Dalcanton, JJ; Dodelson, S; Doi, M; Dong, F; Eisenstein, DJ; Evans, ML; Fan, XH; Feldman, PD; Finkbeiner, DP; Friedman, SD; Frieman, JA; Fukugita, M; Gal, RR; Gillespie, B; Glazebrook, K; Gonzalez, CF; Gray, J; Grebel, EK; Grodnicki, L; Gunn, JE; Gurbani, VK; Hall, PB; Hao, L; Harbeck, D; Harris, FH; Harris, HC; Harvanek, M; Hawley, SL; Heckman, TM; Helmboldt, JF; Hendry, JS; Hennessy, GS; Hindsley, RB; Hogg, DW; Holmgren, DJ; Holtzman, JA; Homer, L; Hui, L; Ichikawa, SI; Ichikawa, T; Inkmann, JP; Ivezic, Z; Jester, S; Johnston, DE; Jordan, B; Jordan, WP; Jorgensen, AM; Juric, M; Kauffmann, G; Kent, SM; Kleinman, SJ; Knapp, GR; Kniazev, AY; Kron, RG; Krzesinski, J; Kunszt, PZ; Kuropatkin, N; Lamb, DQ; Lampeitl, H; Laubscher, BE; Lee, BC; Leger, RF; Li, N; Lidz, A; Lin, H; Loh, YS; Long, DC; Loveday, J; Lupton, RH; Malik, T; Margon, B; McGehee, PM; McKay, TA; Meiksin, A; Miknaitis, GA; Moorthy, BK; Munn, JA; Murphy, T; Nakajima, R; Narayanan, VK; Nash, T; Neilsen, EH; Newberg, HJ; Newman, PR; Nichol, RC; Nicinski, T; Nieto-Santisteban, M; Nitta, A; Odenkirchen, M; Okamura, S; Ostriker, JP; Owen, R; Padmanabhan, N; Peoples, J; Pier, JR; Pindor, B; Pope, AC; Quinn, TR; Rafikov, RR; Raymond, SN; Richards, GT; Richmond, MW; Rix, HW; Rockosi, CM; Schaye, J; Schlegel, DJ; Schneider, DP; Schroeder, J; Scranton, R; Sekiguchi, M; Seljak, U; Sergey, G; Sesar, B; Sheldon, E; Shimasaku, K; Siegmund, WA; Silvestri, NM; Sinisgalli, AJ; Sirko, E; Smith, JA; Smolcic, V; Snedden, SA; Stebbins, A; Steinhardt, C; Stinson, G; Stoughton, C; Strateva, IV; Strauss, MA; Subbarao, M; Szalay, AS; Szapudi, I; Szkody, P; Tasca, L; Tegmark, M; Thakar, AR; Tremonti, C; Tucker, DL; Uomoto, A; Vanden Berk, DE; Vandenberg, J; Vogeley, MS; Voges, W; Vogt, NP; Walkowicz, LM; Weinberg, DH; West, AA; White, SDM; Wilhite, BC; Willman, B; Xu, YZ; Yanny, B; Yarger, J; Yasuda, N; Yip, CW; Yocum, DR; York, DG; Zakamska, NL; Zehavi, I; Zheng, W; Zibetti, S; Zucker, DB
    The Sloan Digital Sky Survey (SDSS) has validated and made publicly available its First Data Release. This consists of 2099 deg(2) of five-band (u, g, r, i, z) imaging data, 186,240 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 1360 deg(2) of this area, and tables of measured parameters from these data. The imaging data go to a depth of r approximate to 22.6 and are photometrically and astrometrically calibrated to 2% rms and 100 mas rms per coordinate, respectively. The spectra cover the range 3800-9200 Angstrom, with a resolution of 1800-2100. This paper describes the characteristics of the data with emphasis on improvements since the release of commissioning data (the SDSS Early Data Release) and serves as a pointer to extensive published and on-line documentation of the survey.