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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').
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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

6831 results found.

  1. GRB 171022A: Fermi GBM detection
  2. GRB 171022A: Fermi-LAT detection
  3. Swift Trigger 781740 is not a burst
  4. GRB 171020A: Swift-XRT refined Analysis
  5. GRB 171020A: Confirmation of OT fading
  6. GRB 171010B: Swift-XRT afterglow detection
  7. INTEGRAL SPI-ACS observation of IceCube-171015A
  8. GRB 171010A : Optical observations from HCT
  9. BAT trigger 778435 is not a GRB.
  10. GRB 171010B: Swift-XRT observations
  11. GRB 171010B: Fermi GBM detection
  12. GRB 171010A: Fermi GBM observation
  13. GRB 171010A: Swift-XRT afterglow detection
  14. GRB 171010A: optical observations
  15. GRB 171010A: Fermi-LAT detection
  16. GRB 171007A: Fermi GBM observation
  17. GRB 171007A: Swift-XRT refined Analysis
  18. GRB 171004A: Swift-XRT refined Analysis
  19. LIGO/Virgo G299232: LOFAR follow-up
  20. GRB 171001A: Swift-XRT refined Analysis
  21. GRB 171001A: IRSF Observation
  22. 3.6m Devasthal Optical Telescope observations of GRB 170428A
  23. Further Swift-XRT observations of IceCube 170922A
  24. IceCube-170922A: Swift-XRT observations
  25. IceCube-170922A: HAWC follow-up
  26. INTEGRAL SPI-ACS observation of AMON IceCube-170922A
  27. GRB 170921A: Swift-XRT refined Analysis
  28. GRB 170921B: Fermi GBM detection
  29. LIGO/Virgo G297595: NIR Observations following GW170814
  30. GRB 170912A: Swift-XRT refined Analysis
  31. GRB 170912B: Swift-XRT refined Analysis
  32. GRB 170912B: Fermi GBM observations
  33. LIGO/Virgo G298936: Konus-Wind observations
  34. LIGO/Virgo G299232: Konus-Wind observations
  35. GRB 170911A: Fermi GBM observation
  36. LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
  37. LIGO/Virgo G299232: Swift-XRT sources
  38. GRB 170906C: optical observations
  39. GRB 170906B: Fermi GBM detection
  40. GRB 170906A: Fermi GBM detection
  41. GRB 170906A: Swift-XRT refined Analysis
  42. GRB 170906C: Swift-XRT refined Analysis
  43. GRB 170906A: Fermi-LAT detection
  44. GRB 170903A: Fermi GBM observation
  45. LIGO/Virgo G298389: Fermi GBM Flux Upper Limits
  46. LIGO/Virgo G299232: LOFAR follow-up
  47. GRB 170903A: Swift-XRT refined Analysis
  48. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  49. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  50. LIGO/Virgo G298048: Possible Plateau in Ks band revealed by continued Gemini-South observations
  51. LIGO/Virgo G298048: Continued Gemini South observations
  52. GRB 170831A: Fermi GBM detection
  53. GRB 170830A: Fermi GBM observation
  54. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  55. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  56. LIGO/Virgo G299232: WHT non-detection u-band optical transient
  57. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  58. LIGO/Virgo G298936: HAWC follow-up
  59. GRB 170827A: Swift-XRT refined Analysis
  60. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  61. GRB 170826B: Fermi GBM detection
  62. GRB 170826A: Fermi GBM detection
  63. LIGO/Virgo G298936: Astrosat CZTI upper limits
  64. LIGO/Virgo G299232: Astrosat CZTI upper limits
  65. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  66. LIGO/Virgo G298389: HAWC follow-up
  67. LIGO/Virgo G299232: INTEGRAL search for a prompt gamma-ray counterpart
  68. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  69. LIGO/Virgo G298936 TAROT/TZAC observations
  70. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  71. LIGO/Virgo G298936 : Fermi-LAT search for a high-energy gamma-ray counterpart
  72. LIGO/Virgo G298936: AGILE GRID observations
  73. LIGO/Virgo G298936: AGILE MCAL observations
  74. GRB 170822A: Swift-XRT refined Analysis
  75. LIGO/Virgo G298048: TOROS Spectra observation with CASLEO
  76. LIGO/Virgo G298048: On the kick velocity and age of the binary Neutron Stars Progenitor
  77. LIGO/Virgo G298389 : Fermi-LAT search for a high-energy gamma-ray counterpart
  78. LIGO/Virgo G298048: Possible X-ray detection with Swift
  79. LIGO/Virgo G298389: INTEGRAL search for a prompt gamma-ray counterpart
  80. LIGO/VIRGO G298048: SALT optical spectra of the candidate optical/NIR counterpart of the gravitational wave G298048 in NGC4993.
  81. LIGO/Virgo G298389: Identification of a GW Burst Candidate
  82. LIGO/Virgo G298048: optical spectral energy distribution of SSS17a
  83. GRB 170818A: Fermi GBM detection
  84. LIGO/Virgo G298048: Archival VLA observations
  85. LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
  86. GRB 170817B: Fermi GBM detection
  87. LIGO/Virgo G298048 : Fermi-LAT search for a high-energy gamma-ray counterpart
  88. GRB 170817A: Fermi GBM detection
  89. LIGO/Virgo G298048: Astrosat CZTI upper limits
  90. GRB 170816A: Fermi GBM detection
  91. LIGO/Virgo G297595: Swift-XRT sources
  92. LIGO/Virgo G297595: Konus-Wind observations
  93. GRB 170813A: Fermi GBM observation
  94. LIGO/Virgo G297595 : Fermi-LAT search for high-energy gamma-ray counterpart
  95. LIGO/Virgo G297595: INTEGRAL search for a prompt gamma-ray counterpart
  96. GRB 170813A: Swift-XRT refined Analysis
  97. GRB 170728B: 15 GHz upper limits from AMI
  98. GRB 170810A: Swift-XRT refined Analysis
  99. GRB 170810A: Fermi GBM observation
  100. GRB 170810A: Fermi-LAT detection

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