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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: Lick/KAIT Follow-Up Observations
  2. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  3. LIGO/Virgo S190425z: MAXI/GSC Observations
  4. LIGO/Virgo S190425z: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  5. LIGO/Virgo S190425z: SAGUARO follow-up observations
  6. LIGO/Virgo S190425z: INTEGRAL prompt observation
  7. LIGO/Virgo S190425z Global MASTER-Net observations report
  8. Fermi GRB190425.09 Global MASTER-Net observations report
  9. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  10. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  11. GRB 190422A: Swift/UVOT Upper Limits
  12. LIGO/Virgo S190408an: Liverpool Telescope follow-up imaging observations
  13. LIGO/Virgo S190421ar: MAXI/GSC Observations
  14. Swift GRB190422.96 Global MASTER-Net observations report
  15. Fermi GRB190422.96 Global MASTER-Net observations report
  16. Fermi GRB190422.67 Global MASTER-Net observations report
  17. LIGO/Virgo S190421ar: Fermi-GBM Observations
  18. LIGO/Virgo S190421ar Global MASTER-Net observations report
  19. AT LIGO-Virgo S190421ar: AGILE GRID observations
  20. LIGO-Virgo S190421ar: AGILE MCAL observations
  21. LIGO/Virgo S190408an: INTEGRAL follow-up observations
  22. Fermi GRB190420.98 Global MASTER-Net observations report
  23. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  24. Fermi GRB190419.41 Global MASTER-Net observations report
  25. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  26. Fermi GRB190418.92 Global MASTER-Net observations report
  27. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  28. GRB 190326A: Swift XRT and UVOT follow-up observations
  29. Fermi GRB190417.46 Global MASTER-Net observations report
  30. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  31. Fermi GRB190415.17 Global MASTER-Net observations report
  32. LIGO/Virgo S190412m: Palomar Gattini-IR Wide-field Infrared Follow-up
  33. LIGO/Virgo S190412m: GOTO optical coverage - no notable counterparts
  34. LIGO/Virgo S190412m: J-GEM optical/NIR follow-up observations
  35. LIGO/Virgo S190412m: Fermi-GBM Observations
  36. LIGO/Virgo S190412m: MAXI/GSC Observations
  37. LIGO-Virgo S190412m: AGILE GRID observations
  38. LIGO/Virgo S190408an: ATLAS observations of the S190412m skymap
  39. LIGO/Virgo S190412m: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  40. LIGO/Virgo S190412m: MASTER early alert observation
  41. LIGO/Virgo S190408an: GROND Observations of MASTER OT J154209.55-431742.2
  42. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  43. IceCube-190331A: Swift-XRT Follow-up Observations
  44. GRB 190409A: ground analysis reveals a likely spurious event
  45. LIGO/Virgo S190408an: MASTER OT J231043.63+470956.4 BOOTES-4 and 10.4m GTC follow-up observations
  46. LIGO/Virgo S190408an: MAXI/GSC Observations
  47. LIGO/Virgo S190408an: GRAWITA optical observations of MASTER OT J231043.63+470956.4
  48. LIGO/Virgo S190408an: CALET Observations
  49. LIGO/Virgo S190408an: TMTS Optical Observation
  50. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  51. LIGO/Virgo S190408an: HMT optical observations
  52. LIGO/Virgo S190408an: MASTER 3 OT's more detection
  53. LIGO-Virgo S190408an: further AGILE GRID observations after T0
  54. LIGO/Virgo S190408an: SAGUARO follow-up observations
  55. LIGO/Virgo S190408an: MASTER OT detection
  56. LIGO/Virgo S190408an: KMTNet observation
  57. LIGO-Virgo S190408an: AGILE GRID observations
  58. LIGO/Virgo S190408an: MASTER Global Robotic Net optical observations
  59. LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
  60. LIGO-Virgo S190408an: AGILE MCAL observations
  61. GRB 190404C: Swift-XRT afterglow detection
  62. Fermi TriggNum 576054086 (GRB 1904204.29) / MASTER OT J071404.52+550304.2: CrAO optical observations
  63. Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
  64. GRB 190404C: Swift-XRT observations
  65. Swift GRB 190331B: Further Swift-XRT observations
  66. GRB190404C: GROWTH-India discovery of optical counterpart
  67. GRB 190404B: Tiled Swift observations
  68. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  69. GRB 190331B: BOOTES-3/YA optical observations
  70. GRB 190331B: Swift observations of a ground-detected burst
  71. Fermi-LAT Gamma-ray Observations of IceCube-190331A
  72. IceCube-190331A: MASTER optical follow-up observations
  73. GRB 190331B: Swift ToO observations
  74. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  75. GRB 190326A: 2.2m CAHA telescope optical limit
  76. Swift Trigger 895479: Detection of GRO J2058+42
  77. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  78. Swift Trigger 895257: Detection of GRO J2058+42 in outburst
  79. GRB 190324A: Swift/UVOT Observations
  80. GRB190324A: MASTER OT observations
  81. Further Chandra observations of GW170817 ~581-583 days since merger
  82. GRB 190324A: Swift-XRT observations
  83. SWIFT GRB190324.95 Global MASTER-Net observations report
  84. SWIFT GRB190323.85 Global MASTER-Net observations report
  85. Swift detection of LS I +61 303
  86. Correction: Chandra observations of GW170817 ~581 days since merger
  87. Chandra observations of GW170817 ~581 days since merger
  88. Swift Trigger 894268: Detection of GRO J2058+42 in outburst
  89. GRB 190114C: photometric detection of a SN component
  90. GRB 190320A: Swift/UVOT Upper Limits
  91. GRB190320A: MASTER GRB counterpart decay
  92. SWIFT GRB190320.05 Global MASTER-Net observations report
  93. GRB 190320A: Swift-XRT observations
  94. Fermi trigger 574140965 / GRB190313.15: MASTER Global Robotic Net optical observation
  95. GRB 190311A: Swift/UVOT Detection
  96. GRB 190311A: Mondy optical observations
  97. GRB 190311A: Liverpool Telescope observations
  98. GRB 190311A: NOT optical counterpart
  99. GRB190305A: MASTER Global Robotic Net optical observation
  100. GRB190311A: OAO observations

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