List of publications for Justin Schaefer while at UWYO ------------------------------------------------------------------------------- _______________________________________________________________________________ Conference Posters and Proceedings ------------------------------------------------------------------------------- AAS Abstract for June 2004 Authors: Justin J. Schaefer and Michael S. Brotherton The University of Wyoming, Department of Physics and Astronomy, P.O. Box 3905, Laramie, Wyoming 82072. Title: FR II BALQSOs in DR2 of the SDSS Abstract: FR II BALQSOs may be an even rarer form of quasar than has been previously suggested. These Broad Absorption Line Quasi-Stellar Objects (BALQSOs) are extremely radio luminous and display classic large-scale double-lobed radio structures (FR II morphology). Previous samples of BALQSOs have shown very few significant radio detections, much less exhibit such an extreme radio morphology. The radio morphology, as well as the BAL regions intrinsic to this type of quasar suggest that these objects are at an early stage in quasar development (Gregg et al. 2000). However due to the limited sample size of previous surveys only two FR II BALQSOs have been found and published in the literature. In order to expand the sample size we conducted an archival search through the first Data Release (DR1) of the Sloan Digital Sky Survey (SDSS). This produced three new candidate FR II BALQSOs from a population of 1026 quasars with FIRST (Faint Images of the Radio Sky at Twenty-centimeters) counterparts. More recently we searched the entire second Data Release (DR2) of the SDSS and determined that although our sample size had doubled, (2243 objects with FIRST counterparts), no new FR II BALQSO candidates were found. We discuss the implications and make a multi-wavelength statistical comparison of the FR II BALQSO candidates with other sample quasar populations. We present a catalog comprised of the radio, and optical/UV absorption-line properties of these candidate FR II BALQSOs. ______________________________________________________________________________ ______________________________________________________________________________ Title: FR II BALQSOs in the SDSS Authors: Schaefer, J. J.; Brotherton, M. S. Affiliation: AA(University of Wyoming), AB(University of Wyoming) Journal: American Astronomical Society Meeting 203, #56.11 Publication Date: 12/2003 Origin: AAS Abstract Copyright: (c) 2003: American Astronomical Society Bibliographic Code: 2003AAS...203.5611S Abstract FR II BALQSOs are a rare form of BALQSO, of which only two have been published in literature. These Broad Absorption Line Quasi-Stellar Objects(BALQSOs) are extremely radio luminous and display classic large-scale double-lobed radio structures. Due to the vast quantity of objects observed by the SDSS, more of these FR II BALQSOs have been found. These objects, currently representing only a minute fraction of known BALQSOs, may soon have a sample large enough to enable statistical analysis,and comparisons to other BALQSOs. We present a catalog comprised of FR II BALQSOs found in current releases of the Sloan Digital Sky Survey (SDSS). This research is funded by Wyoming NASA Space Grant Consortium, NASA Grant #NGT-40102 and by Wyoming NASA EPSCoR NASA Grant #NCC5-578. ______________________________________________________________________________ ______________________________________________________________________________ Title: A Search for Variability Among Cool Blue Degenerate Stars Authors: Rudkin, M. A.; Oswalt, T. D.; Johnston, K. B.; Wennerstrom, E. A.; Schaefer, J. J.; Bochanski, J. J. Affiliation: AA(Florida Institute of Technology), AB(Florida Institute of Technology), AC(Florida Institute of Technology), AD(Rhodes College), AE(University of Wyoming), AF(University of Washington) Journal: American Astronomical Society Meeting 203, #54.03 Publication Date: 12/2003 Origin: AAS Abstract Copyright: (c) 2003: American Astronomical Society Bibliographic Code: 2003AAS...203.5403R Abstract Replace these paragraphs with your abstract. We encourage you to include a sentence acknowledging your funding agency. Presented here are preliminary results of a photometric survey of cool white dwarf stars. CCD-based times series observations have been obtained for white dwarfs (WDs) with absolute magnitude Mv > +15 and color 0.2 < V-I < 1.4. Several hours of continuous observations have been obtained for each target in an attempt to detect microvariability in the temperature regime where collisionally induced absorption due to molecular hydrogen is possible. The minimum time resolution achieved for individual objects is 10-300sec, depending upon target brightness. In the sample of several dozen cool WDs observed so far, no periodic variability larger than ?2% has been detected. Such objects have good potential to be used as faint (V > +17) OIR flux standards for large aperture telescopes. Observations were obtained remotely using the SARA Observatory 0.9m automated telescope at Kitt Peak, which is operated by the Southeastern Association for Research in Astronomy. This research was supported by NASA Graduate Student Research Program NGT5-50450, NASA AISR subcontract Y701296 through the University of Arizona, the Stellar Astronomy and Astrophysics program (NSF AST-0206225) and the SARA Research Experiences for Undergraduates program (NSF AST-0097616). ______________________________________________________________________________ ______________________________________________________________________________ Title: XMM-Newton Observations of the FR II Radio-Loud BAL Quasar FIRST J1016+5209 Authors: Schaefer, Justin J.; Brotherton, Michael S.; Gregg, Michael D.; Becker, Robert H.; Laurent-Muehleisen, Sally A.; Lacy, Mark; White, Richard L.; Affiliation: AA AB (University of Wyoming),AC AC(University of California, Lawrence Livermore National Laboratory), AE(University of California), AF(Caltech), AG(STScI). Conference Proceedings: AGN Physics with the Sloan Digital Sky Survey ASP Conference Series, Vol. 311, 329, 2004 G.T. Richards and P.B. Hall, eds. Abstract: We have detected FIRST J101614.3+520916 with the XMM-Newton X-ray observatory. FIRST J1016+5209, one of the most extreme radio-loud broad absorption line (BAL) quasars so far discovered, is a Fanaroff-Riley type II (FR II) radio source. We find the X-ray flux is low in comparison to the radio flux, indicating X-ray absorption. We have measured optical-X-ray spectral indicies and X-ray hardness ratios (HR). FIRST J1016+5209 is relatively X-ray bright compared to radio- quiet BAL quasars. Despite the low counts, we have determined that a simple high-column-density absorber does not match the soft optical-X-ray spectral index and the HR simultaneously, requiring a more complex model (e.g., one that includes a partial covering X-ray absorber). ______________________________________________________________________________ ______________________________________________________________________________ Title: a Search for Variability in Cool White Dwarf STARS* Authors: Oswalt, Terry D.; Johnston, Kyle; Rudkin, Merissa; Schaefer, Justin; Bochanski, John Affiliation: AA(Florida Institute of Technology), AB(Florida Institute of Technology), AC(Florida Institute of Technology), AD(University of Wyoming), AE(University of Washington) Journal: White Dwarfs: Galactic and Cosmologic Probes, 25th meeting of the IAU, Joint Discussion 5, 16-17 July 2003, Sydney, Australia Publication Date: 00/2003 Origin: IAU Bibliographic Code: 2003IAUJD...5E..38O Abstract Preliminary results of a photometric survey of cool white dwarf stars are presented. CCD-based time series observations have been obtained for white dwarfs with absolute magnitude Mv > +15 and color 0.5 < V-I < 1.3. Several hours of continuous observations are being obtained for each target in an attempt to establish the frequency of microvariability in the temperature regime where collisionally induced absorption due to molecular hydrogen is possible. In the sample of over two dozen cool white dwarfs observed so far no periodic or nonperiodic variability larger than ~0.01 magnitude has been detected. The minimum time resolution achieved for individual objects is ten seconds to three minutes depending upon target brightness. The potential for such objects to be used as faint (V>+17) OIR flux standards for large aperture telescopes is discussed. Support for this project from the U.S. National Science Foundation is gratefully acknowledged (AST-0097616 and AST-0206115). *Observations were obtained with the SARA 0.9-m automated telescope at Kitt Peak in Arizona which is operated by the Southeastern Association for Research in Astronomy (www.saraobservatory.org) ______________________________________________________________________________ ______________________________________________________________________________ The Continuing Search for Variability Among Cool White Dwarfs Schaefer, J. J.; Oswalt, T. D.; Johnston, K. B.; Rudkin, M.; Heinz, T. AA(SARA, University of Wyoming), AB(SARA, Florida Institute of Technology), AC(SARA, Florida Institute of Technology), AD(SARA, Florida Institute of Technology), AE(SARA, Florida Institute of Technology) American Astronomical Society Meeting 201, #119.01 Publication Date: 12/2002 Origin:AAS Abstract Copyright: (c) 2002: American Astronomical Society Bibliographic Code: 2002AAS...20111901S The Continuing Search for Variability Among Cool White Dwarfs Justin J. Schaefer University of Wyoming Department of Physics and Astronomy P.O.Box 3905 Laramie,Wyoming 82071 USA (schaefju@uwyo.edu) Terry D. Oswalt, Kyle Johnston, Merissa Rudkin, Tamalyn Heinz Florida Institute of Technology and the SARA Observatory Department of Physics & Space Sciences 150 West University Boulevard Melbourne Florida 32901 USA (oswalt@luyten.astro.fit.edu, kyjohnst@fit.edu, mrudkin@astro.fit.edu, theinz@fit.edu) ABSTRACT We present BVRI photometry of eleven binaries with white dwarf (WD) components. The observations were obtained at the SARA 0.9-meter telescope on Kitt Peak during the summer of 2002. Standard system (B-V), (V-R) and (R-I) color indices of four white dwarfs were determined. This data will be used to estimate the WD cooling ages in wide WD+dM binaries, as part of our ongoing research program to determine the chromospheric activity-age relation for M dwarf stars. Time-series differential photometry was also collected for eight cool white dwarfs as part of a program to explore the variability in the low luminosity, low temperature regime of the WD cooling track. We failed to detect any variability greater than ~0.04 magnitudes in these stars. Several nights of differential photometry data were collected on the DAO WD + K dwarf short-period variable HS1136+6646. From the light variations we determined a likely orbital period of 0.825 +/-0.009 days. Strong evidence is presented for two other possible periods within this light curve, possibly indicative of rotational modulation by the WD component. We gratefully acknowledge support from the National Science Foundation, which funds the SARA Research Experiences for Undergraduates program via grant AST- 0097616 to Florida Tech. One of us (TDO) also acknowledges partial support for this work from NASA (subcontract Y701296) and the NSF (AST 0206115). ------------------------------------------------------------------------------- _______________________________________________________________________________ GCN Circulars ------------------------------------------------------------------------------- TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1584 SUBJECT: GRB021004, Optical Observations DATE: 02/10/05 20:39:28 GMT FROM: Richard J. Cool at U of Wyoming R. J. Cool, J. J. Schaefer (University of Wyoming) reporting on behalf of the University of Wyoming GRB Response Team under the direction of R. Canterna: We observed the optical afterglow of GRB 021004 (GCN #1564) with the Red Buttes Observatory 0.6 meter telescope, operated through the University of Wyoming, between 4:37 UT and 6:25 UT on October 5 2002. All observations were completed in the R-band under unfavorable conditions. We find R-band magnitudes for two epochs: UT R_mag ====================== 04:52:36 19.14 06:20:25 19.23 Typical errors on these values are +/- 0.1 mag. Calibration was completed assuming the USNO star from Weidinger (GCN #1573) has an R magnitude of 15.64. Further analysis and observations are scheduled in the coming days. This message may be cited. Richard Cool University of Wyoming 307/766-8918 riccool@uwyo.edu ______________________________________________________________________________ ______________________________________________________________________________ TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1681 SUBJECT: GRB 021016: Optical Observations DATE: 02/11/11 20:34:49 GMT FROM: Melissa Nysewander at UNC,Chapel Hill J. Schaefer, S. Savage, S. Hwang, R. Canterna (U. Wyoming), M. Nysewander, and D. Reichart (U. North Carolina) report: We observed the entire ~200 square arcminute error box of GRB 021016 (GCN 1639, 1640, 1641) with the 0.6-meter Red Buttes Observatory telescope beginning 15 hours, 39 hours, and 63 hours after the burst. We integrated without filter for ~1 hour per pointing x three pointings for each epoch. Visual comparison between our first epoch and the DSS on the 17th revealed no obvious counterpart to the limiting magnitude of the DSS. Visual comparison between our first and second epochs on the 18th and our first and third epochs on the 19th revealed no obvious counterpart to the limiting magnitude of our first epoch, which we estimate to be V ~ 22 mag. Given the large error box and crowed field, we have confirmed this result using the image differencing code ISIS-2 (Alard 2000). _______________________________________________________________________________ _______________________________________________________________________________ TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1685 SUBJECT: GRB 021112: Optical Observations DATE: 02/11/13 00:16:11 GMT FROM: Melissa Nysewander at UNC,Chapel Hill J. Schaefer, S. Savage, R. Canterna (U. Wyoming), M. Nysewander, and D. Reichart (U. North Carolina) report: We observed the inner 90% of the 40-arcminute diameter error circle of GRB 021112 (GCN 1683) with the 0.6-meter Red Buttes Observatory telescope beginning 1.8 hours after the burst. We integrated without filter for 1800 seconds per pointing x four pointings. Visual comparison with the DSS2-Red reveals no obvious counterpart to the limiting magnitude of the DSS. _______________________________________________________________________________ _______________________________________________________________________________ TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1776 SUBJECT: GRB 021112: Evidence for Another Dark Optical Afterglow DATE: 02/12/22 00:16:58 GMT FROM: Melissa Nysewander at UNC,Chapel Hill J. Schaefer, S. Savage, R. Canterna (U. Wyoming), M. Nysewander, D. Reichart (U. North Carolina), A. Henden (USRA/USNO), and D. Lamb (U. Chicago) report on behalf of a larger collaboration: We observed the inner 93% of the 40-arcminute diameter error circle of GRB 021112 (GCN 1682) with the 0.6-meter Red Buttes Observatory telescope beginning 1.8 hours (GCN 1685) and 13.9 days after the burst. For the first epoch observation, we integrated without filter for 1800 seconds per pointing x four pointings. For the second epoch observation, we integrated without filter for 2700 seconds per pointing x four pointings. Unfiltered magnitudes measured with our Apogee AP8P CCD best mimic Rc magnitudes. Using the image subtraction routine ISIS2 (Alard 2000), we find no candidates to the limiting magnitude of our first epoch image, which we measure to be Rc = 21.8 mag (3 sigma), 22.2 mag (2 sigma), and 23.0 mag (1 sigma) using the field calibration of Henden (GCN 1697). We note that the Galactic extinction along this line of sight is approximately A_Rc = 0.52 mag (Schlegel et al. 1998). The candidate of Strolger et al. (GCNs 1684, 1696) sits outside of the above fields. In addition to the arguments presented by Nysewander et al. (GCN 1701), its BVRcIcH spectral flux distribution and low Galactic latitude suggest that it is a low-mass flare star. Dismissing this candidate, this is the deepest non-detection of an optical afterglow beginning within 2.6 hours of a burst (GCN 1699). Alard, C. 2000, A&AS 114, 363 Schlegel, D., et al. 1998, ApJ, 500, 525 _______________________________________________________________________________ _______________________________________________________________________________ TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2042 SUBJECT: GRB 030329 RBO V Optical Observations DATE: 03/03/31 07:51:21 GMT FROM: Justin Schaefer at U of Wyoming J. Schaefer, S. Savage (University of Wyoming) Report on behalf of the University of Wyoming GRB response team and the FUN GRB collaboration: We observed the optical afterglow of GRB 030329, identified in (GCN 1986), in the Johnson V-Band with the RBO 0.6m telescope at Red Buttes Wyoming. We obtained 6, 180s exposures on March 30th UT. The observations were carried out under fair to poor conditions. Aperture photometry was performed and calibrated utilizing the standards reported by Henden et al., (GCN 2023). We initially measured the magnitude of the OT to be V=15.57 +/- 0.01 at 02:59UT which faded by 0.06 during the short observational period. Further observations are currently being undertaken, and more data for the V filter will follow. This message may be cited _______________________________________________________________________________ _______________________________________________________________________________ TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2062 SUBJECT: GRB030329 Further RBO Optical Observations DATE: 03/04/01 19:19:49 GMT FROM: Justin Schaefer at U of Wyoming S. Savage, J. Schaefer, D. Gibbs (University of Wyoming) Report on behalf of the University of Wyoming GRB response team and the FUN GRB collaboration: We observed the optical afterglow of GRB 030329, identified in Torii (GCN 1986), in the Johnson V filter with the RBO 0.6m telescope at Red Buttes Wyoming. We obtained 25, 300s exposures. Observations were undertaken between 02:26UT and 6:00UT, on March 31st. The observations were carried out under fair seeing conditions. Aperture photometry was performed and calibrated utilizing the standards reported by Henden et al., (GCN 2023). We initially measured the magnitude of the OT to be V=16.71, which faded by 0.15 mag during our observational period; however, there appeared to be a brightening. Errors were on average +/- 0.018. Further aperture photometry is being performed and observations are planned. This message may be cited. _______________________________________________________________________________ _______________________________________________________________________________ TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2137 SUBJECT: GRB 030413: Optical Observations DATE: 03/04/15 16:15:43 GMT FROM: Melissa Nysewander at UNC,Chapel Hill J. Schaefer, D. Gibbs, M. Nysewander, R. Canterna, and D. Reichart report on behalf of the FUN GRB collaboration: We imaged the entire 314 sq arcmin error box of the IPN burst, GRB 030413 (Hurley et al. GCN 2135) with the UWYO 0.6m Red Buttes Observatory (RBO) Telescope beginning 21.701 hours after the burst (April 14.2199 UT). We integrated in Rc for 1200s in five pointings. Visual comparison to the DSS reveals no optical transient. Through calibration to five USNO A-2.0 stars, we estimate the (S/N=3) limiting magnitude to be Rc=19.2. _______________________________________________________________________________ _______________________________________________________________________________ TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2250 SUBJECT: GRB 030416: Optical Observations DATE: 03/05/27 15:19:05 GMT FROM: Jane Moran at U.North Carolina A. Henden, J. Silvay, J. Moran, R. Soule, D. Reichart, J. Schaefer, R. Canterna, and B. Scoggins report on behalf of the USNO, UWYO, and UNC GRB teams of the FUN GRB collaboration: We observed the entire 14 arcminute diameter error circle of XRF 030416 (Jernigan et al., GCN 2209) in BVRcIc beginning 15.4 hours after the burst, despite a bright moon. We report the following limiting magnitudes: Start Start Time Filter Integration Limiting Telescope Calibration Date Since GRB Time (sec) Magnitude Catalog (hours) x Pointings (3 sigma) Apr 17.103 15.391 Rc 6000 x 1 19.8 0.6-m RBO* USNO A2.0 Apr 17.143 16.361 B 300 x 1 20.1 1.3-m USNO USNO A2.0 Apr 17.149 16.502 V 300 x 1 20.9 1.3-m USNO ACT Apr 17.155 16.643 Rc 300 x 1 20.4 1.3-m USNO USNO A2.0 Apr 17.160 16.784 Ic 300 x 1 19.9 1.3-m USNO USNO B1.0 Apr 20.143 88.454 Rc 2160 x 1 22.3 1.3-m USNO USNO A2.0 * RBO = Red Buttes Observatory Using the image subtraction routine ISIS2 (Alard 2000, A&AS, 114, 363), we find no transient sources in either of our Rc images of April 17th when compared to our Rc image of April 20th. _______________________________________________________________________________ _______________________________________________________________________________