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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"

3140 results found.

  1. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  2. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  3. LIGO/Virgo S190425z: RATIR Observations of Galaxies
  4. LIGO/Virgo S190425z: YAHPT Optical Observation
  5. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  6. LIGO/Virgo S190425z: KMTNet Observation
  7. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  8. LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
  9. LIGO/Virgo S190425z - GROWTH-India follow-up of two ZTF candidates
  10. LIGO/Virgo S190425z: KPED Follow-Up Observations
  11. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  12. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  13. LIGO/Virgo S190425z: MMT Follow-Up Observations
  14. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  15. LIGO/Virgo S190425z: Identification of a GW compact binary merger candidate
  16. Fermi GRB190425.09 Global MASTER-Net observations report
  17. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  18. Fermi GRB190422.67 Global MASTER-Net observations report
  19. LIGO/Virgo S190421ar Global MASTER-Net observations report
  20. LIGO/Virgo S190408an: INTEGRAL follow-up observations
  21. Fermi GRB190420.98 Global MASTER-Net observations report
  22. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  23. Fermi GRB190419.41 Global MASTER-Net observations report
  24. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  25. IceCube-190331A: Swift-XRT Follow-up Observations
  26. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  27. LIGO/Virgo S190408an: TMTS Optical Observation
  28. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  29. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  30. Swift Trigger 895479: Detection of GRO J2058+42
  31. Swift Trigger 895257: Detection of GRO J2058+42 in outburst
  32. Swift Trigger 894268: Detection of GRO J2058+42 in outburst
  33. Fermi Trigger 574850558 / GRB 190321363: BALROG localization
  34. Fermi Trigger 574345067 / GRB 190315512: BALROG localization
  35. GRB 190311A: Mondy optical observations
  36. Fermi Trigger 574080135 / GRB 190312446: BALROG localization
  37. GRB 190305A: Swift-XRT observations
  38. GRB190219A: MASTER Global Robotic Net optical observation
  39. GRB 190202A: SAO RAS further optical observations
  40. Swift Trigger 887541: MASTER inspect
  41. GRB 190204A: Swift detection of a burst with a possible optical counterpart
  42. GRB 190202A: Swift detection of a burst with an optical counterpart
  43. Improved IPN error box for GRB 190129B
  44. GRB 190129B: Swift-XRT candidate afterglow detection
  45. GRB 190123A: Fermi GBM observation
  46. GRB 190114C: RTT150 optical observations
  47. GRB 190114A: NOEMA detection of the mm afterglow
  48. GRB 190114C: KMTNet optical observation
  49. GRB 190114C: LSGT optical observation
  50. GRB 190114B: NOT optical counterpart
  51. GRB190109A: MITSuME Akeno optical upper limits
  52. IPN triangulation of GRB 190103A (long)
  53. Konus-Wind observation of GRB 190106A
  54. GRB 190106A : TSHAO optical observations
  55. GRB 190103A: AstroSat CZTI detection
  56. GRB 190103A: AGILE/MCAL detection of a burst
  57. GRB 181228A: Swift detection of a burst
  58. GRB 181222B: Global MASTER Net observations of short bright Fermi GRB
  59. Swift Trigger 878504 is not astrophysical
  60. GRB 181222A: MAXI/GSC detection
  61. GRB 181213A: AbAO optical observations
  62. GRB 181212A: Fermi GBM Detection
  63. GRB 181202A: Swift/UVOT Detection
  64. GRB 181202A: Global MASTER-Net optical observations
  65. GRB 181202A: Swift detection of a burst with an optical counterpart
  66. GRB 181201A MASTER-Net OT continued observation
  67. Konus-Wind observation of GRB 181121A
  68. Konus-Wind observation of GRB 181110A
  69. GRB 181103A: AbAO optical upper limit
  70. IPN Triangulation of GRB 181028A (long)
  71. GRB 181013A: Global MASTER Net optical observations
  72. GRB 181008B: Global MASTER Net optical inspection
  73. GRB 181010A: MASTER-Argentina OT detection
  74. GRB 180923A: MASTER inspection MAXI/GSC error box
  75. GRB 180923A: MAXI/GSC detection
  76. GRB 180914B: MASTER OT automatic dtection
  77. GRB180809B: MASTER OT observation
  78. Fermi Trigger 554765006: MASTER optical inspection
  79. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  80. GRB 180722A: MASTER optical observation
  81. GRB180715B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 553369644)
  82. IceCube-171106A: MASTER optical observation
  83. GRB 180706A: GOTO optical limits
  84. GRB 180704A: Swift detection of a burst
  85. IPN Triangulation of GRB 180626C (short)
  86. Konus-Wind observation of GRB 180623A
  87. GRB 180624A: GROND observations
  88. GRB 180620A: Swift-BAT refined analysis
  89. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  90. GRB 180605A: Fermi GBM observation
  91. IPN Triangulation of GRB 180523A
  92. GRB 180510B: Swift detection of a burst with an optical counterpart
  93. GRB 180411A: Swift-BAT refined analysis
  94. Konus-Wind observation of GRB 180404C
  95. IPN Triangulation of GRB 180404C (long)
  96. GRB 180404C CALET Gamma-Ray Burst Monitor detection
  97. Fermi GBM triggers 544628550/180405571, 544542853/180404579, 544531428/180404447 are not GRBs
  98. GRB 180404A: MASTER-OAFA OT observation
  99. GRB 180329B: Swift detection of a burst with an optical afterglow
  100. GRB 180324A: Enhanced Swift-XRT position

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