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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

124 results found.

  1. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  2. LIGO/Virgo S190425z: Swift UVOT - no new sources identified, and a summary of the Swift UVOT processing of GW triggers.
  3. LIGO/Virgo S190425z: No counterpart candidate in Zadko-GRANDMA observations.
  4. LIGO/Virgo S190425z: CAHA-GRANDMA Observation of the Swift UVOT Source
  5. LIGO/Virgo S190425z: Konus-Wind observations
  6. IceCube-190504A: MASTER optical monitoring analysis
  7. LIGO/Virgo S190503bf: AstroSat CZTI upper limits
  8. LIGO/Virgo S190425z: Insight-HXMT observation and counterpart search
  9. LIGO/Virgo S190425z: Konkoly imaging of target galaxies
  10. LIGO/Virgo S190425z: Gaia Photometric Alerts transient candidates
  11. LIGO/Virgo S190425z: Gaia Photometric Alerts transient candidate
  12. LIGO/Virgo S190425z: Keck/MOSFIRE NIR spectroscopy of PS19qp (= AT 2019ebq)
  13. LIGO/Virgo S190425z: ZTF pre-detections of Gaia19bpt AT2019ehz
  14. LIGO/Virgo S190425z: Gaia Photometric Alerts transient candidates
  15. LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
  16. LIGO/Virgo S190425z: 1.3-m optical imaging of UVOT transient field
  17. LIGO/Virgo S190425z: Gaia Photometric Alerts transient candidate
  18. LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
  19. LIGO/Virgo S190425z: MASTER detection of the faint flare in SDSS Seyfert galaxy z = 0.09
  20. LIGO/Virgo S190425z: DECam Observations of the UVOT Candidate Region
  21. LIGO/Virgo S190425z: RATIR non-detection of the Swift/UVOT source
  22. LIGO/Virgo S190425z: VISTA K-band observations of the Swift/UVOT Transient
  23. LIGO/Virgo S190425z : IRSF/SIRIUS NIR photometric follow-up observation of the Swift/UVOT Transient
  24. LIGO/Virgo S190425z: MASTER explanation of the nature of an optical flash detected by a Swift as a short flare on a fast-moving WISE brown
  25. LIGO/Virgo S190425z: No i-band detection of the Swift/UVOT transient in SkyMapper observations
  26. LIGO/Virgo S190425z: 1.5m OSN and 10.4m imaging of the UVOT source field
  27. LIGO/Virgo S190425z: Spectroscopic observations of two ZTF candidates with SOAR
  28. LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
  29. LIGO/Virgo S190425z: NOT photometry of ZTF19aasckkq
  30. LIGO/Virgo S190425z: No source found at UVOT source location at 6 hrs after LVC report
  31. LIGO/Virgo S190425z: SVOM/GWAC-F60A observations
  32. LIGO/Virgo S190425z: Liverpool Telescope imaging of ZTF19aasckkq
  33. LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient in ASAS-SN observations hours before and after discovery
  34. LIGO/Virgo S190425z: Potential host galaxy of UVOT candidate counterpart found in BLISS
  35. LIGO/Virgo S190425z: Additional Candidates from the Zwicky Transient Facility
  36. LIGO/Virgo S190425z: ASAS-SN observations
  37. LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient with Las Cumbres Observatory
  38. LIGO/Virgo S190425z: Pre-discovery NIR limits of the UVOT transient candidate from Gattini-IR
  39. LIGO/Virgo S190425z: Swift/UVOT and XRT pre-images at the position of the potential Swift/UVOT counterpart
  40. LIGO/Virgo S190425z: GROWTH-India observations of the Swift/UVOT transient
  41. Correction to GCN Circular 24301: LIGO/Virgo S190425z: Lulin observations of the Swift/UVOT transient
  42. LIGO/Virgo S190425z: ZTF photometry of the UVOT transient candidate hours before discovery
  43. LIGO/Virgo S190425z: Lulin observations of the Swift/UVOT transient
  44. LIGO/Virgo S190425z: Transient found in Swift/UVOT counterpart search
  45. LIGO/Virgo S190425z: Further confirmation for the classification of PS19qp/AT 2019ebq as a supernova
  46. LIGO/Virgo S190425z: CNEOST Optical Observations
  47. LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
  48. LIGO/Virgo S190425z: Lulin Observations of Counterpart Search
  49. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  50. LIGO/Virgo S190425z - ePESSTO+ spectrum of candidate PS19qu
  51. LIGO/Virgo S190425z: Lijiang 2.4-m Telescope Follow-up Observations
  52. LIGO/Virgo S190425z: Fermi-LAT search for a high-energy gamma-ray counterpart
  53. LIGO/Virgo S190425z: Additional Pan-STARRS transients in the skymap
  54. LIGO/Virgo S190425z: ANU 2.3m early observations of ZTF19aarykkb
  55. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  56. SUBJECT: LIGO/Virgo S190425z: GRAWITA LBT spectroscopic observations
  57. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  58. Baksan Neutrino Observatory Alert 190405.62: Global MASTER-Net:LIGO/Virgo S190425z: PanSTARR OT AT2019ebq/PS19qp
  59. LIGO/Virgo S190425z: Pierre Auger Observatory follow-up
  60. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  61. LIGO/Virgo S190425z: RATIR Observations of Galaxies
  62. LIGO/Virgo S190425z: YAHPT Optical Observation
  63. LIGO/Virgo S190425z: Keck NIR spectroscopy shows AT2019ebq is a supernova
  64. LIGO/Virgo S190425z: Nearby Galaxies in the Updated Localization Volume
  65. LIGO/Virgo S190425z: J-GEM spectroscopic observations of AT2019ebq/PS19qp with Subaru/FOCAS
  66. LIGO/Virgo S190425z: GROND observations of AT2019ebq/PS19qp
  67. LIGO/Virgo S190425z: Updated localization from LIGO and Virgo data
  68. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  69. LIGO/Virgo S190425z: AMI-LA radio observations of two ZTF afterglow candidates.
  70. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  71. LIGO/Virgo S190425z: GOTO observations
  72. LIGO/Virgo S190425z: ZTF pre-merger limits on PS1 candidates
  73. LIGO/Virgo S190425z: LWA1 observations
  74. LIGO/Virgo S190425z: DCT ZTF19aarykkb spectroscopy
  75. LIGO/Virgo S190425z : IRSF/SIRIUS NIR photometry of ZTF19aarykkb and ZTF19aarzaod
  76. LIGO/Virgo S190425z: CALET Observations
  77. LIGO/Virgo S190425z - ePESSTO+ spectrum of PS19qp shows red featureless source at z=0.037
  78. LIGO/Virgo S190425z: KMTNet Observation
  79. LIGO/Virgo S190425z - ePESSTO+ NTT spectrum of candidate PS19qo
  80. LIGO/Virgo S190425z: ZTF19aarzaod 1.5m OSN imaging and 10.4m GTC spectroscopy
  81. LIGO/Virgo S190425z: Insight-HXMT/HE observation
  82. LIGO/Virgo S190425z: Swope follow-up observations
  83. LIGO/Virgo S190425z - ePESSTO+ NTT observations
  84. LIGO/Virgo S190425z: Pan-STARRS observations and transients in the skymap
  85. LIGO/Virgo S190425z: ZTF19aarzaod WHT spectroscopy
  86. LIGO/Virgo S190425z: GRAWITA TNG observations of ZTF19aarzaod
  87. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  88. LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
  89. LIGO/Virgo S190425z: SALT spectroscopy of ZTF19aarzaod as a likely type II supernova
  90. LIGO/Virgo S190425z: Liverpool Telescope spectroscopy of ZTF19aarykkb
  91. LIGO/Virgo S190425z: Liverpool Telescope non-detections of ATLAS candidates
  92. LIGO/Virgo S190425z - GROWTH-India follow-up of two ZTF candidates
  93. LIGO/Virgo S190425z - HCT spectroscopy
  94. LIGO/Virgo S190425z: STARE2 simultaneous L-band radio observations
  95. LIGO/Virgo S190425z: KPED Follow-Up Observations
  96. LIGO/Virgo S190425z: ATLAS observations of the S190425z skymap
  97. LIGO/Virgo S190425z: OVRO-LWA simultaneous low frequency radio observations of localization region
  98. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  99. LIGO/Virgo S190425z: ZTF19aarzaod Imaging from Las Cumbres Observatory
  100. LIGO/Virgo S190425z: Lulin Follow-Up Observations

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