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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"

45787 results found.

  1. Fermi GRB 240720A: Global MASTER-Net observations report
  2. GRB 240720A: AstroSat CZTI detection
  3. GRB 240720A: Fermi GBM observation
  4. GRB 240720A: Swift detection of a burst
  5. Swift GRB240720.02: Global MASTER-Net observations report
  6. Konus-Wind detection of GRB 240718A
  7. GRB 240713A: SVOM/GRM observation
  8. Fermi GRB 240718A: Global MASTER-Net observations report
  9. LAT GRB240718.27: Global MASTER-Net observations report
  10. GRB 240718A: Fermi GBM Observation
  11. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  12. GRB 240718A: Fermi-LAT Detection
  13. GRB 240718A: SVOM/GRM observation
  14. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  15. GRB 240718A: Fermi GBM Final Real-time Localization
  16. GRB 240712A: Swift-BAT refined analysis
  17. GRB 240716A: GECAM-B detection of a long burst
  18. SVOM/GRM In-Flight Trigger of GRB 240716A
  19. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  20. GRB 240713A: 2.2m CAHA optical limit
  21. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  22. GRB 240715A: Swift/UVOT observations of the XRT sources.
  23. GRB 240715A: Swift-XRT observations
  24. GRB240713A: Swift/UVOT Upper LImits
  25. EP240708a: X-ray follow-up observations with Swift/XRT
  26. GRB 240715A: GECAM-C detection of a short burst
  27. Konus-Wind detection of GRB 240715A
  28. LIGO/Virgo/KAGRA S240716b: Updated Sky localization
  29. GRB 240713A: Swift-XRT observations
  30. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  31. GRB 240712A: Swift-XRT refined Analysis
  32. SVOM/GRM In-Flight Trigger of GRB 240715A
  33. GRB 240713A: LAST optical upper limit
  34. LIGO/Virgo/KAGRA S240716b: Identification of a GW compact binary merger candidate
  35. GRB 240715A: Swift ToO observations
  36. Fermi GRB 240715A: Global MASTER-Net observations report
  37. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  38. GRB 240715A: Fermi GBM Observation
  39. GRB 240712A ATCA radio observations
  40. GRB240715A: GRANDMA Optical Upper Limits
  41. IPN triangulation of GRB 240715A (short)
  42. GW s240422ed: Swift UVOT follow-up
  43. GRB 240712A: Swift/UVOT Upper Limits
  44. EP-WXT flaring star and the optical flaring activity during its decay phase
  45. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  46. The EP-WXT source triggered on July 14th is likely a flaring star
  47. GRB 240715A: Fermi GBM Final Real-time Localization
  48. GRB 240713A: Tiled Swift observations
  49. GRB 240713A: J-band upper limit from WINTER
  50. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  51. GRB 240713A: JinShan optical upper limits
  52. GRB 240713A: OHP/T120 optical upper limit
  53. GRB240713A: X-ray follow-up observation with EP-FXT (duplicate submission of GCN 36859)
  54. GRB240713A: X-ray follow-up observation with EP-FXT
  55. GRB 240713B: AstroSat CZTI detection of a long burst
  56. GRB240713A: Optical upper limit with Kinder observations
  57. Fermi Sub-threshold Observation of GRB240713A
  58. GRB240713A: TAROT and GRANDMA Observations of SVOM/ECLAIRs GRB240713A
  59. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  60. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  61. EP240708a: GSP optical upper limit
  62. GRB 240712A: Swift detection of a burst
  63. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  64. GRB 240711A: Fermi GBM Final Real-time Localization
  65. Fermi trigger No 742405878: Global MASTER-Net observations report
  66. LIGO/Virgo/KAGRA S240627by: Updated Sky localization and EM Bright Classification
  67. Fermi trigger No 742317942: Global MASTER-Net observations report
  68. EP240708a: KAIT optical upper limit
  69. Fermi GRB 240710A: Global MASTER-Net observations report
  70. GRB 240710A: Fermi GBM Final Real-time Localization
  71. EP240708a: NOT optical observations
  72. EP240708a: SVOM/C-GFT optical upper limit
  73. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  74. EP240708a: Optical upper limits with Kinder observations
  75. EP240708a: EP-WXT detection of a fast X-ray transient
  76. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  77. EP240703b: GSP optical upper limit
  78. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  79. GRB 240705A: Fermi GBM Final Real-time Localization
  80. EP240703b: TRT optical upper limits
  81. EP240703a: TRT further optical observation
  82. EP240702a: TRT optical upper limits
  83. Konus-Wind detection of GRB 240627A
  84. IPN triangulation of GRB 240628B (short)
  85. LIGO/Virgo/KAGRA S240705at: Updated Sky localization
  86. EP240703a and EP240703b: Swift/XRT upper limits
  87. LIGO/Virgo/KAGRA S240705at: Identification of a GW compact binary merger candidate
  88. EP240703a: KAIT optical upper limit
  89. EP240703a: BTA observations
  90. EP240703c: Kinder optical follow-up and Swift XRT observations
  91. EP240703a: BOOTES-3 optical upper limit
  92. EP240703a: Liverpool Telescope optical follow-up observations
  93. EP240703a/GRB 240703A: TRT optical candidate likely not real
  94. EP240703a: Kinder optical follow-up observations
  95. EP240703c: EP-WXT detection of an X-ray transient
  96. LIGO/Virgo/KAGRA S240703ad: Updated Sky localization
  97. LIGO/Virgo/KAGRA S240703ad: Identification of a GW compact binary merger candidate
  98. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  99. IPN triangulation of GRB 240627A
  100. GRB 240619A: Host galaxy redshift from VLT/X-shooter

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