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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"

3147 results found.

  1. LIGO/Virgo S191109d: No significant candidates in FRAM-TAROT-GRANDMA observations
  2. LIGO/Virgo S191105e: No significant candidates in FRAM-TAROT-GRANDMA observations
  3. LIGO/Virgo S191109d: AstroSat CZTI upper limits
  4. GRB 191031D: Chandra upper limit
  5. Fermi trigger No 594592184: Global MASTER-Net observations report
  6. Fermi trigger No 594557071: Global MASTER-Net observations report
  7. Baksan Neutrino Observatory Alert 191102.06: Global MASTER-Net observations report
  8. Swift GRB191031.89: Global MASTER-Net observations report
  9. GRB 191025B: AstroSat CZTI detection
  10. GRB 191028B: MASTER optical observation
  11. Konus-Wind observation of GRB 191025B
  12. IPN triangulation of GRB 191027A
  13. IPN triangulation of GRB 191025B (short)
  14. GRB 191025B: Insight-HXMT/HE detection
  15. GRB 191026A: Fermi GBM Final Real-time Localization
  16. GRB191024A: MASTER optical observation
  17. GRB 191024A: Swift detection of a burst
  18. Fermi trigger No 593176520: Global MASTER-Net observations report
  19. Fermi trigger No 592818648: Global MASTER-Net observations report
  20. GRB 191011A: correction of reported magnitudes
  21. GRB 191009A: Fermi GBM Final Real-time Localization
  22. Fermi trigger No 592211224: Global MASTER-Net observations report
  23. LIGO/Virgo S190930s: no counterpart candidate in the SVOM/GWAC observations
  24. Swift GRB191004.9: Global MASTER-Net OT detection
  25. LIGO/Virgo S190930t: AT2019rpn, AT2019rpj CrAO continued optical photometry
  26. LIGO/Virgo S190930t: Lulin Follow-up Observations of AT2019rpn and AT2019rpj
  27. LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
  28. LIGO/Virgo S190930t: Transient found in Swift/UVOT counterpart search
  29. Fermi trigger No 591604915: Global MASTER-Net observations report
  30. LIGO/Virgo S190930t: Global MASTER-Net observations report
  31. LIGO/Virgo S190930t: Upper limits from IceCube neutrino searches
  32. Fermi trigger No 591321287: Global MASTER-Net observations report
  33. LIGO/Virgo S190923y: No significant candidates in TAROT-GRANDMA observations
  34. IceCube-190922A: Upper limits from a search for additional neutrino events in IceCube
  35. Fermi-LAT Gamma-ray Observations of IceCube-190922A
  36. IceCube-190922A - HAWC follow-up
  37. IceCube-190922A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  38. IceCube-190922A - IceCube observation of a high-energy neutrino candidate event
  39. LIGO/Virgo S190915ak: No significant candidates in TAROT-GRANDMA observations
  40. LIGO/Virgo S190910h: No significant candidates in TAROT-GRANDMA observations
  41. Fermi trigger No 590335819: Global MASTER-Net observations report
  42. LIGO/Virgo S190915ak: Global MASTER-Net observations report
  43. LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
  44. LIGO/Virgo S190814bv: No counterpart candidate after completion of GRAWITA VST-ESO PARANAL transient survey.
  45. LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
  46. Update to the Fermi GBM Localizations
  47. LIGO/Virgo S190910d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  48. LIGO/Virgo S190901ap : No significant candidates found in GRANDMA citizen science observations
  49. LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
  50. LIGO/Virgo S190901ap: NOT spectroscopy of AT2019pjv
  51. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  52. LIGO/Virgo S190901ap: MASTER OT J171434.95+280725.6/AT2019pjv detection
  53. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  54. GRB 190829A: MeerKAT radio observation
  55. LIGO/Virgo S190901ap Global MASTER-Net observations report
  56. Fermi trigger No 589065714 Global MASTER-Net observations report
  57. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  58. LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
  59. GRB 190830B: Fermi GBM Final Real-time Localization
  60. GRB 190829A: NOT optical afterglow detection and spectroscopy
  61. LIGO/Virgo S190828j: No Counterparts in DDOTI/OAN Optical Observations
  62. LIGO/Virgo S190828l: No counterpart candidates in KAIT observations
  63. LIGO/Virgo S190829u Global MASTER-Net observations report
  64. LIGO/Virgo S190828j: No transient candidates in CALET observations
  65. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  66. LIGO/Virgo S190828j: Upper limits from IceCube neutrino searches
  67. GRB 190824A: Fermi GBM Final Real-time Localization
  68. Fermi trigger No 588115134 Global MASTER-Net observations report
  69. Fermi GBM-190816: MASTER-Net optical observation report
  70. LIGO/Virgo S190814bv: No radio counterpart detected in ASKAP observations
  71. LIGO/Virgo S190814bv: No Optical Counterpart Candidates in Second-Epoch Lick/KAIT Observations
  72. Fermi trigger No 588100239 Global MASTER-Net observations report
  73. LIGO/Virgo S190814bv: Further Pan-STARRS observations and transient sources
  74. IceCube-190819A - HAWC follow-up
  75. LIGO/Virgo S190814bv: GRAWITA TNG NIR imaging of AT2019nqq and AT2019nqc
  76. LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  77. LIGO/Virgo S190814bv : No Counterpart Candidates in Continued Galaxy Targeted Search with Magellan
  78. S190814bv: MASTER analysis of DECam-GROWTH candidates
  79. GRB 190816A: Swift detection of a burst
  80. LIGO/Virgo S190814bv : No Counterpart Candidates in Galaxy Targeted Search with Magellan
  81. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  82. Fermi trigger No 587505927 Global MASTER-Net observations report
  83. LIGO/Virgo S190814bv Global MASTER-Net observations report
  84. LIGO/Virgo S190814bv: No counterpart candidates in KAIT observations
  85. LIGO/Virgo S190814bv: no counterpart candidates in Thacher imaging
  86. LIGO/Virgo S190814bv: no counterpart candidates in Swope imaging
  87. LIGO/Virgo S190814bv: no counterpart candidates in Nickel/Direct imaging and non-detections of 2019nmd and 2019nme
  88. LIGO/Virgo S190814bv: KMTNet observation
  89. LIGO/Virgo S190814bv Global MASTER-Net optical observations
  90. LIGO/Virgo S190814bv: Liverpool Telescope imaging of selected galaxies
  91. LIGO/Virgo S190814bv: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  92. IPN triangulation of GRB 190810A (short)
  93. GRB 190810A: Fermi GBM Final Real-time Localization
  94. GRB 190808B: Fermi GBM Final Real-time Localization
  95. Fermi trigger No 586788607 Global MASTER-Net observations report
  96. GRB 190804B: MAXI/GSC detection
  97. Fermi trigger No 586574612 Global MASTER-Net observations report
  98. GRB 190731A: no OT detected by MASTER
  99. Fermi trigger No 586305505 Global MASTER-Net observations report
  100. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215

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