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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').
Advanced Search

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"

20960 results found.

  1. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  2. GRB 160104A: Spectroscopic observations from 10.4m GTC
  3. GRB 160104A: Mini-GWAC upper limit during prompt emission phase
  4. GRB 160104A: GWAC upper limit during prompt emission phase
  5. GRB 160104A: MITSuME Okayama Ks-band upper-limit
  6. LIGO/Virgo G211117: Fermi/LAT observations
  7. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  8. LIGO/Virgo G211117: Gemini classification of 7 Pan-STARRS transients
  9. LIGO/Virgo G211117: LOFAR follow-up
  10. GRB 160102A: Swift-XRT observations
  11. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  12. LIGO/Virgo G211117: PESSTO classification of Pan-STARRS transients
  13. LIGO/Virgo G211117: MASTER OTs 26.XII.2015 - 01.I.2016
  14. LIGO/Virgo G211117: CSS/CRTS observations on 29/30 Dec 2015 UT
  15. GRB 160102A: Tiled Swift observations
  16. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28 - 30
  17. GRB 160101A: Swift/UVOT Detection
  18. GRB 160101A: Swift-XRT afterglow detection
  19. GRB 160101A: Tiled Swift observations
  20. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  21. LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
  22. LIGO/Virgo G211117: MAXI/GSC observations
  23. MASTER-NET observations of V404Cyg Swift Trigger 668877
  24. LIGO/Virgo G211117: Liverpool Telescope followup of EM candidates
  25. LIGO/Virgo G211117: VLA follow-up
  26. Trigger 668877: Swift detection of V 404 Cyg
  27. LIGO/Virgo G211117: MAGIC very-high energy gamma-ray observations
  28. LIGO/Virgo G211117: INAF TNG follow-up of MASTER OT J020906.21+013800.1
  29. LIGO/Virgo G211117: OAO-WFC NIR follow-up observations
  30. LIGO/Virgo G211117: SkyMapper observations and transient candidate
  31. V404Cyg Swift Trigger 668097: CrAO RT-22 radio observations
  32. LIGO/Virgo G211117: MASTER Observations of the 3 iPTF candidates
  33. V404Cyg Swift Trigger 668097: AbAO optical observations
  34. GRB 151228B: Swift/UVOT Detection
  35. LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
  36. LIGO/Virgo G211117: List of near-term future observation regions by Project Mini-GWAC of SVOM
  37. LIGO/Virgo G211117: iPTF Optical Transient Candidates
  38. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29
  39. GRB 151229A: Swift/UVOT observations
  40. LIGO/Virgo G211117: Further Swift-XRT sources
  41. GRB 151228A: T60 observations
  42. LIGO/Virgo G211117: DESGW program observations with DECam
  43. LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
  44. LIGO/Virgo G211117: Fermi GBM Observations
  45. LIGO/Virgo G211117: Optical follow-up with Kanata telescope
  46. LIGO/Virgo G211117: MASTER Observations and Inspection + OT
  47. LIGO/Virgo G211117: Pan-STARRS1 observations 2015-12-28
  48. LIGO/Virgo G211117: INAF VST-ESO PARANAL observations
  49. LIGO/Virgo G211117: Further Swift-XRT sources
  50. LIGO/Virgo G211117: Swift-XRT sources
  51. LIGO/Virgo G211117: SWASP optical observations
  52. LIGO/Virgo G211117: MASTER possible OT detection at the begining of inspection
  53. V404Cyg Swift Trigger 668097: TSHAO optical observations
  54. V404Cyg Swift Trigger 668097: MASTER-Tunka optical wake up detection
  55. GRB 151215A: TSHAO optical observations
  56. GRB151215A: Continued P60 Observations
  57. GRB151215A: Early optical light curve from pt5m, La Palma
  58. GRB151215A: Swift/UVOT detection
  59. GRB 151215A: GROND Detection of the Optical/NIR Afterglow
  60. GRB151215A: P60 Optical Afterglow Candidate
  61. LIGO/Virgo G184098: LOFAR follow-up
  62. GRB151212A: Swift/UVOT observations
  63. GRB 151212A: GROND Optical Afterglow Candidate
  64. GRB 151212A: Swift-XRT afterglow detection
  65. GRB 151212A: Tiled Swift observations
  66. GRB 151210A: Swift/UVOT Upper Limits
  67. GRB 151210A: GROND Afterglow Confirmation
  68. GRB 151210A: Optical afterglow candidate from LCOGT-Cerro Tololo
  69. GRB 151205C: Optical follow-up observations at Kiso
  70. GRB 151205B: Deep GROND Upper limits
  71. GRB 151205B: further Swift-XRT observations
  72. GRB 151205C: Swift-XRT observations
  73. GRB 151205C: Tiled Swift observations
  74. GRB 151205B: MASTER-NET early optical observations
  75. GRB 151205A: Garching Telescope Upper Limit
  76. GRB151205B: Initial UVOT observations
  77. GRB 151205B: Swift-XRT observations
  78. GRB 151205A: Swift/UVOT Upper Limits
  79. LIGO/Virgo G184098: Results of of 2nd epoch of ASKAP follow-up
  80. GRB 151122A: Further Swift-XRT observations, no afterglow detected.
  81. GRB 151127A: Swift/UVOT Upper Limits
  82. GRB 151127A: GROND K-band upper limit
  83. GRB 151127A: LCOGT-SSO optical upper limits
  84. GRB 151122A: Swift/UVOT Observations
  85. GRB 151122A: Swift-XRT observations
  86. GRB 151122A: Swift ToO observations
  87. GRB 151027A: Maidanak optical observations
  88. GRB 151120A: Swift-XRT afterglow detection
  89. GRB 151120A: Swift ToO observations
  90. GRB 151120A: GROND optical/NIR afterglow
  91. LIGO/Virgo G194575: Fermi GBM Observations
  92. 610 MHz detection of GRB 151027A with the GMRT
  93. GRB 151118A: Early optical limit from pt5m, La Palma
  94. GRB 151027A: SAO RAS and Mt. Terskol observations
  95. GRB 151118A: Swift/UVOT Upper Limits
  96. GRB GRB 151118A: MASTER-NET optical observations
  97. GRB 151118A: Optical observations from OSN
  98. GRB151027A; Optical observations
  99. GMRT radio detection of GRB 151027A
  100. GRB 151114A: GROND Detection of the Optical/NIR Afterglow Candidate

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