• Dynamics of Ringed Barred Spiral Galaxies. I. Surface Photometry and Kinematics of NGC 1433 and NGC 6300 

  Buta, Ronald J.; Ryder, Stuart D.; Madsen, Gregory J.; Wesson, Karen; Crocker, D. A.; Combes, F. (2001)

  This paper presents new near-infrared images and surface photometry and Hα Fabry-Perot radial velocities for NGC 1433 and NGC 6300, two large and previously well-studied nearby ringed barred spiral galaxies. Stellar ...
• Search for Time-independent Neutrino Emission from Astrophysical Sources with 3 yr of IceCube Data 

  Santander, Marcos (2013-12-03)

  We present the results of a search for neutrino point sources using the IceCube data collected between 2008 April and 2011 May with three partially completed configurations of the detector: the 40-, 59-, and 79-string ...
• Searches for Extended and Point-like Neutrino Sources with Four Years of IceCube Data 

  Santander, Marcos (2014-11-12)

  We present results on searches for point-like sources of neutrinos using four years of IceCube data, including the first year of data from the completed 86 string detector. The total livetime of the combined data set is ...
• A Hubble Space Telescope Optical and Ground-Based Near-Infrared Study of the Giant Nuclear Ring in ESO 565-11 

  Buta, Ronald J.; Crocker, D. A.; Byrd, G. G. (1999)

  We present multiband Wide Field Planetary Camera 2 images of the central regions of ESO 565-11, a peculiar southern barred galaxy recently shown to have the largest known example of a circumnuclear starburst ring. We also ...
• Observation of Cosmic-ray Anisotropy with the Icetop Air Shower Array 

  Santander, Marcos (2013-02-15)

  We report on the observation of anisotropy in the arrival direction distribution of cosmic rays at PeV energies. The analysis is based on data taken between 2009 and 2012 with the IceTop air shower array at the south pole. ...
• Circumnuclear Star Formation in the Early-Type Resonance Ring Barred Spiral Galaxy NGC 1326 

  Buta, Ronald J.; Treuthardt, Patrick M.; Byrd, G. G.; Crocker, D. A. (2000)

  We present multiband WFPC2 images of the nuclear ring of NGC 1326, an early-type southern barred spiral in the nearby Fornax galaxy cluster. The ring is a typical example of a 1 kpc–sized star-forming ring located in the ...
• Investigating Broadband Variability of the TeV Blazar 1ES 1959+ 650 

  Santander, Marcos (2014-12-03)

  We summarize broadband observations of the TeV-emitting blazar 1ES 1959+650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift Ultraviolet and Optical ...
• Multiwavelength Study of Quiescent States of MRK 421 with Unprecedented Hard X-ray Coverage Provided by NuSTAR in 2013 

  Santander, Marcos (2016-03-09)

  We present coordinated multiwavelength observations of the bright, nearby BL Lacertae object Mrk 421 taken in 2013 January–March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, VERITAS, and other collaborations and ...
• First NuSTAR Observations of MRK 501 within a Radio to TeV Multi-instrument Campaign 

  Santander, Marcos (2015-10-08)

  We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 2013 April 1 and August 10, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. ...
• VERITAS Detection of γ-ray Flaring Activity from the BL Lac Object 1ES 1727+ 502 during Bright Moonlight Observations 

  Santander, Marcos (2015-07-27)

  During moonlit nights, observations with ground-based Cherenkov telescopes at very high energies (VHEs, E ˃ 100 GeV) are constrained since the photomultiplier tubes (PMTs) in the telescope camera are extremely sensitive ...
• Searches for Time-dependent Neutrino Sources with IceCube Data from 2008 to 2012 

  Santander, Marcos (2015-06-30)

  In this paper searches for flaring astrophysical neutrino sources and sources with periodic emission with the IceCube neutrino telescope are presented. In contrast to time-integrated searches, where steady emission is ...
• A Technique for Separating the Gravitational Torques of Bars and Spirals in Disk Galaxies 

  Buta, Ronald J.; Block, D. L.; Knapen, J. H. (American Astronomical Society, 2003-09)

  We describe a Fourier-based method of separating bars from spirals in near-infrared images. The method takes advantage of the fact that a bar is typically a feature with a relatively fixed position angle and uses the simple ...
• A Search for Pulsations from Geminga above 100 GeV with VERITAS 

  Santander, Marcos (American Astronomical Society, 2015-02-09)

  We present the results of 71.6 hr of observations of the Geminga pulsar (PSR J0633+1746) with the VERITAS very-high-energy gamma-ray telescope array. Data taken with VERITAS between 2007 November and 2013 February were ...
• The Ringed Spiral Galaxy NGC 4622. I. Photometry, Kinematics, and the Case for Two Strong Leading Outer Spiral Arms 

  Buta, Ronald J.; Byrd, Gene G.; Freeman, Tarsh (American Astronomical Society, 2003-02)

  The intriguing nearly face-on southern ringed spiral galaxy NGC 4622, the first galaxy definitively shown to have leading spiral structure, is revisited in this paper with new images from the Hubble Space Telescope's (HST) ...
• Maffei 1 with the Hubble Space Telescope 

  Buta, Ronald J.; McCall, Marshall L. (American Astronomical Society, 2003-03)

  High-resolution R, I, and Hα images of the center of Maffei 1, the nearest normal giant elliptical galaxy (M^0/_v = -20.9), have been acquired with the Hubble Space Telescope. At its distance of 3.0 Mpc, 1 pixel in the ...
• NGC 7217: A Spheroid-dominated, Early-Type Resonance Ring Spiral Galaxy 

  Buta, R.; Van Driel, W.; Braine, J.; Combes, F.; Wakamatsu, K.; Sofue, Y.; Tomita, A. (1995-09)

  NGC 7217 is a well-known northern spiral galaxy which is characterized by flocculent spiral structure and a series of three optical ringlike zones: a nuclear ring 21" in diameter, a weak inner ring 63" in diameter, and a ...
• A Search for Very High-Energy Gamma Rays from the Missing Link Binary Pulsar J1023+0038 with VERITAS 

  Santander, Marcos (2016-11-08)

  The binary millisecond radio pulsar PSR J1023+0038 exhibits many characteristics similar to the gamma-ray binary system PSR B1259–63/LS 2883, making it an ideal candidate for the study of high-energy nonthermal emission. ...
• VERITAS and Fermi-LAT Observations of TeV Gamma-Ray Sources Discovered by HAWC in the 2HWC Catalog 

  Santander, Marcos (American Astronomical Society, )

  The High Altitude Water Cherenkov (HAWC) collaboration recently published their 2HWC catalog, listing 39 very high energy (VHE; > 100GEV) gamma-ray sources based on 507 days of observation. Among these, 19 sources are not ...
• Tev Gamma-Ray Observations of the Galactic Center Ridge by Veritas 

  Santander, Marcos (2016-04-22)

  The Galactic Center ridge has been observed extensively in the past by both GeV and TeV gamma-ray instruments revealing a wealth of structure, including a diffuse component and the point sources G0.9+0.1 (a composite ...
• A Multimessenger Picture of the Flaring Blazar TXS 0506+056: Implications for High-energy Neutrino Emission and Cosmic-Ray Acceleration 

  Santander, Marcos (2018-08-31)

  Detection of the IceCube-170922A neutrino coincident with the flaring blazar TXS 0506+056, the first and only ~3σ high-energy neutrino source association to date, offers a potential breakthrough in our understanding of ...

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