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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21093 results found.

  1. LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
  2. LIGO/Virgo S190426c: GRAWITA transients from Asiago Schmidt wide field observations
  3. LIGO/Virgo S190425z: DECam Observations of the UVOT Candidate Region
  4. LIGO/Virgo S190426c: Continued LOAO Observation
  5. LIGO/Virgo S190425z: VISTA K-band observations of the Swift/UVOT Transient
  6. GRB 190427A: Swift/UVOT Upper Limits
  7. LIGO/Virgo S190426c: Additional Candidates from the Zwicky Transient Facility
  8. LIGO/Virgo S190426c: Continued infrared wide-field search with Palomar Gattini-IR
  9. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  10. 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
  11. LIGO/Virgo S190425z: No i-band detection of the Swift/UVOT transient in SkyMapper observations
  12. LIGO/Virgo S190426c: ASAS-SN observations
  13. LIGO/Virgo S190425z: Spectroscopic observations of two ZTF candidates with SOAR
  14. LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
  15. LIGO/Virgo S190425z: SVOM/GWAC-F60A observations
  16. LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient in ASAS-SN observations hours before and after discovery
  17. LIGO/Virgo S190425z: Potential host galaxy of UVOT candidate counterpart found in BLISS
  18. LIGO/Virgo S190425z: Additional Candidates from the Zwicky Transient Facility
  19. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  20. LIGO/Virgo S190425z: ASAS-SN observations
  21. LIGO/Virgo S190425z: GROWTH-India observations of the Swift/UVOT transient
  22. Correction to GCN Circular 24301: LIGO/Virgo S190425z: Lulin observations of the Swift/UVOT transient
  23. LIGO/Virgo S190425z: ZTF photometry of the UVOT transient candidate hours before discovery
  24. LIGO/Virgo S190425z: Lulin observations of the Swift/UVOT transient
  25. LIGO/Virgo S190426c: RATIR Optical and NIR Observations of Galaxies
  26. LIGO/Virgo S190426c: J-GEM optical/NIR follow-up observations
  27. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  28. LIGO/Virgo S190425z: Further confirmation for the classification of PS19qp/AT 2019ebq as a supernova
  29. Fermi GRB190427.19 Global MASTER-Net observations report
  30. LIGO/Virgo S190426c: MMT Follow-Up Observations
  31. LIGO/Virgo S190426c: GOTO optical coverage - no notable counterparts
  32. GRB 190427A: Lick/Nickel telescope optical observations
  33. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  34. GRB 190427A: COATLI Optical Observations
  35. LIGO/Virgo S190426c: CNEOST Optical Observations
  36. LIGO/Virgo S190425z: CNEOST Optical Observations
  37. LIGO/Virgo S190426c: Infrared Wide-field Search with Palomar Gattini-IR
  38. LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
  39. GRB 190427A: RATIR Optical and NIR Observations
  40. LIGO/Virgo S190426c: Nanshan/NEXT Observation of Galaxies
  41. LIGO/Virgo S190426c: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  42. LIGO/Virgo S190426c: CALET Observations
  43. LIGO/Virgo S190426c: Imaging confirmation and host spectroscopy of DG19vkgf
  44. LIGO/Virgo S190425z: Lulin Observations of Counterpart Search
  45. LIGO/Virgo S190426c: Swift-XRT sources
  46. GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
  47. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  48. LIGO/Virgo S190425z - ePESSTO+ spectrum of candidate PS19qu
  49. LIGO/Virgo S190426c: Red and blue transients identified with DECam
  50. LIGO/Virgo S190425z: Lijiang 2.4-m Telescope Follow-up Observations
  51. GRB 190427A: NOT optical observations
  52. GRB 190427A: Swift-XRT observations
  53. Swift GRB190427.19 Global MASTER-Net observations report
  54. LIGO/Virgo S190425z: ANU 2.3m early observations of ZTF19aarykkb
  55. LIGO/Virgo S190426c: MAXI/GSC Observations
  56. LIGO/Virgo S190426c: Public DECam Observations
  57. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  58. LIGO/Virgo S190426c: STARE2 simultaneous L-band radio observations
  59. LIGO/Virgo S190425z: GRAWITA LBT spectroscopic observations
  60. LIGO/Virgo S190426c: Fermi GBM Observations
  61. LIGO/Virgo S190426c: AGILE-GRID Observations
  62. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  63. Baksan Neutrino Observatory Alert 190405.62: Global MASTER-Net:LIGO/Virgo S190425z: PanSTARR OT AT2019ebq/PS19qp
  64. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  65. LIGO/Virgo S190425z: RATIR Observations of Galaxies
  66. LIGO/Virgo S190426c Global MASTER-Net observations report
  67. LIGO/Virgo S190425z: YAHPT Optical Observation
  68. LIGO/Virgo S190425z: Nearby Galaxies in the Updated Localization Volume
  69. LIGO/Virgo S190425z: J-GEM spectroscopic observations of AT2019ebq/PS19qp with Subaru/FOCAS
  70. LIGO/Virgo S190425z: GROND observations of AT2019ebq/PS19qp
  71. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  72. LIGO/Virgo S190425z: AMI-LA radio observations of two ZTF afterglow candidates.
  73. LIGO/Virgo S190425z: GOTO observations
  74. LIGO/Virgo S190425z: LWA1 observations
  75. LIGO/Virgo S190425z: DCT ZTF19aarykkb spectroscopy
  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 - ePESSTO+ NTT spectrum of candidate PS19qo
  79. LIGO/Virgo S190425z: Swope follow-up observations
  80. LIGO/Virgo S190425z - ePESSTO+ NTT observations
  81. LIGO/Virgo S190425z: Pan-STARRS observations and transients in the skymap
  82. LIGO/Virgo S190425z: ZTF19aarzaod WHT spectroscopy
  83. LIGO/Virgo S190425z: GRAWITA TNG observations of ZTF19aarzaod
  84. LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
  85. LIGO/Virgo S190425z: Liverpool Telescope spectroscopy of ZTF19aarykkb
  86. LIGO/Virgo S190425z - HCT spectroscopy
  87. LIGO/Virgo S190425z: STARE2 simultaneous L-band radio observations
  88. LIGO/Virgo S190425z: KPED Follow-Up Observations
  89. LIGO/Virgo S190425z: ATLAS observations of the S190425z skymap
  90. LIGO/Virgo S190425z: OVRO-LWA simultaneous low frequency radio observations of localization region
  91. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  92. LIGO/Virgo S190425z: Lulin Follow-Up Observations
  93. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  94. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  95. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  96. LIGO/Virgo S190425z: Palomar Gattini-IR wide-field infrared follow-up
  97. LIGO/Virgo S190425z: AGILE-GRID Observations
  98. LIGO/Virgo S190425z: Fermi GBM Observations
  99. LIGO/Virgo S190425z: MMT Follow-Up Observations
  100. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation

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