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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').
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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"

2723 results found.

  1. LIGO/Virgo S190923y: Upper limits from IceCube neutrino searches
  2. Fermi trigger No 590777160: Global MASTER-Net observations report
  3. Baksan Neutrino Observatory Alert 190920.65: Global MASTER-Net observations report
  4. GRB 190919B: FRAM-Auger optical detection
  5. GRB 190919B: Swift-XRT observations
  6. Integral GRB190919.99: Global MASTER-Net observations report
  7. LIGO/Virgo S190915ak: No significant candidates in TAROT-GRANDMA observations
  8. LIGO/Virgo S190910h: No significant candidates in TAROT-GRANDMA observations
  9. LIGO/Virgo S190915ak: no counterpart candidates in the Swift/BAT observations
  10. LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
  11. LIGO/Virgo S190814bv: No counterpart candidate after completion of GRAWITA VST-ESO PARANAL transient survey.
  12. LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
  13. LIGO/Virgo S190910h: Four additional candidates from the Zwicky Transient Facility
  14. Update to the Fermi GBM Localizations
  15. LIGO/Virgo S190910h: Candidates from the Zwicky Transient Facility
  16. LIGO/Virgo S190910h: no counterpart candidates in the Swift/BAT observations
  17. LIGO/Virgo S190910h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  18. LIGO/Virgo S190910d: Candidates from the Zwicky Transient Facility
  19. LIGO/Virgo S190910d: no counterpart candidates in the Swift/BAT Observations
  20. LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
  21. LIGO/Virgo S190814bv: VLA/JAGWAR monitoring of the 50% containment region
  22. GRB 190829A optical observation
  23. LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
  24. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  25. LIGO/Virgo S190901ap: Additional candidates from the Zwicky Transient Facility
  26. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  27. LIGO/Virgo S190901ap: Additional observations from the Zwicky Transient Facility
  28. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  29. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  30. LIGO/Virgo S190901ap: no counterpart candidates in the Swift/BAT Observations
  31. LIGO/Virgo S190901ap: Candidates from the Zwicky Transient Facility
  32. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  33. LIGO/Virgo S190814bv : No significant candidates in TAROT-GRANDMA observations
  34. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  35. LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
  36. LIGO/Virgo S190828l: No counterpart candidates in KAIT observations
  37. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  38. GRB 190828C: Fermi GBM Final Real-time Localization
  39. GRB 190828A: MAXI/GSC detection
  40. Fermi GBM-190816: Eight additional candidates from the Zwicky Transient Facility
  41. LIGO/Virgo S190814bv: Detection of a candidate radio counterpart with ASKAP
  42. LIGO/Virgo S190814bv: LCO Photometry of DG19wxnjc/AT2019npv
  43. LIGO/Virgo S190814bv: MASTER prediscovery and postdiscovery observations DECam candidate DG19wxnjc/AT2019npv field
  44. LIGO/Virgo S190814bv: No Optical Counterpart Candidates in Second-Epoch Lick/KAIT Observations
  45. Fermi GBM-190816: Four additional candidates from the Zwicky Transient Facility
  46. Fermi GBM-190816: One candidate counterpart from the Zwicky Transient Facility
  47. LIGO/Virgo GBM-190816: no counterpart candidates in the Swift/BAT Observations
  48. Fermi GBM-190816: Location-dependent upper limits from INTEGRAL/SPI-ACS prompt observation
  49. IceCube-190819A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  50. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  51. LIGO/Virgo S190814bv : No Counterpart Candidates in Continued Galaxy Targeted Search with Magellan
  52. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  53. LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
  54. LIGO/Virgo S190814bv : No Counterpart Candidates in Galaxy Targeted Search with Magellan
  55. Fermi trigger No 587505927 Global MASTER-Net observations report
  56. LIGO/Virgo S190814bv: No counterpart candidates in KAIT observations
  57. LIGO/Virgo S190814bv: no counterpart candidates in Swope imaging
  58. LIGO/Virgo S190814bv: no counterpart candidates in Keck I MOSFIRE imaging
  59. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  60. LIGO/Virgo S190814bv: No counterpart candidates in the Swift/BAT Observations
  61. LIGO/Virgo S190814bv: GRAWITA TNG imaging of selected galaxies
  62. LIGO/Virgo S190814bv: Liverpool Telescope imaging of selected galaxies
  63. LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
  64. LIGO/Virgo S190814bv: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  65. LIGO/Virgo S190814bv Global MASTER-Net observations report
  66. FRB 190806: MASTER optical observation
  67. Fermi trigger No 586676451 Global MASTER-Net observations report
  68. GRB 190804B: MAXI/GSC detection
  69. Fermi trigger No 586574612 Global MASTER-Net observations report
  70. LIGO/Virgo S190728q: No counterpart candidates in H.E.S.S. observations
  71. LIGO/Virgo S190727h: AstroSat CZTI upper limits
  72. LIGO/Virgo S190728q: MITSuME Okayama and Bisei Follow-Up of ZTF19abjethn (AT2019lvs)
  73. LIGO/Virgo S190728q: Optical transients from Pan-STARRS coverage during first 2 nights
  74. LIGO/Virgo s190728q: ePESSTO+ NTT classification of AT2019lvt as a type-Ia SN
  75. LIGO/Virgo S190728q: No counterpart candidates in KAIT observations
  76. LIGO/Virgo S190728q: Optical Candidate from the Zwicky Transient Facility ZTF19abjethn
  77. LIGO/Virgo S190727h: No counterpart candidates in KAIT observations
  78. Fermi trigger No 585621841 Global MASTER-Net observations report
  79. LIGO/Virgo S190720a: No counterpart candidates in KAIT observations
  80. GRB 190720A: Fermi GBM Final Real-time Localization
  81. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  82. LIGO/Virgo S190720a Global MASTER-Net observations report
  83. LIGO/Virgo S190718y: No counterpart candidates in KAIT observations
  84. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  85. LIGO/Virgo S190718y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  86. GRB 190613B: FRAM-Auger afterglow detection
  87. Fermi trigger No 584977168 Global MASTER-Net observations report
  88. Fermi trigger No 584929684 Global MASTER-Net observations report
  89. IceCube Alert 190712.05 Global MASTER-Net observations report
  90. Fermi trigger No 584583925 Global MASTER-Net observations report
  91. Fermi trigger No 584465880 Global MASTER-Net observations report
  92. Fermi trigger No 584404689 Global MASTER-Net observations report
  93. GRB 190708B: MAXI/GSC detection
  94. LIGO/Virgo S190706ai: No counterpart candidates in KAIT observations
  95. GRB 190706A: MAXI/GSC detection
  96. LIGO/Virgo S190630ag: no counterpart candidate in the SVOM/GWAC observations
  97. GRB 190701A: COATLI Optical Observations
  98. GRB 190701A: Swift detection of a burst
  99. GRB 190630B: Swift-XRT refined Analysis
  100. Fermi trigger No 583567803 Global MASTER-Net observations report

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