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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"

32724 results found.

  1. GRB 240727A: NOT optical observation
  2. GRB 240727A: JinShan optical upper limits
  3. GRB 240727A Bassano Bresciano Observatory upper limit
  4. GRB 240727D: Correction to the GRB name in GCN 36958
  5. GRB 240720B: GRBAlpha detection
  6. GRB 240718A: GRBAlpha detection
  7. GRB 240627A: GRBAlpha detection
  8. Fermi GRB 240726A: Global MASTER-Net observations report
  9. GRB 240727B: Fermi GBM Observation
  10. GRB240529A: VIRT optical transient detection
  11. GRB 240727B: Swift ToO observations
  12. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  13. GRB 240726A: SVOM/GRM observation
  14. GRB240727A: Skynet Optical Afterglow Observations
  15. GRB 240727A: TRT optical afterglow detection
  16. GRB 240727A: KAIT Optical Afterglow Candidate
  17. GRB 240726A: AstroSat CZTI detection of a short burst
  18. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  19. Fermi-LAT gamma-ray observations of IceCube-240725A
  20. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  21. GRB 240720A: Swift-BAT refined analysis
  22. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  23. Fermi-LAT gamma-ray observations of IceCube-240721A
  24. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  25. GRB 240720B: SVOM/GRM observation
  26. Fermi GRB 240720A: Global MASTER-Net observations report
  27. GRB 240720A: AstroSat CZTI detection
  28. GRB 240720A: Fermi GBM observation
  29. Konus-Wind detection of GRB 240718A
  30. GRB 240713A: SVOM/GRM observation
  31. Fermi GRB 240718A: Global MASTER-Net observations report
  32. GRB 240718A: Fermi GBM Observation
  33. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  34. GRB 240718A: Fermi-LAT Detection
  35. GRB 240718A: SVOM/GRM observation
  36. GRB 240712A: Swift-BAT refined analysis
  37. GRB 240716A: GECAM-B detection of a long burst
  38. GRB 240715A: Swift/UVOT observations of the XRT sources.
  39. GRB240713A: Swift/UVOT Upper LImits
  40. EP240708a: X-ray follow-up observations with Swift/XRT
  41. GRB 240715A: GECAM-C detection of a short burst
  42. Konus-Wind detection of GRB 240715A
  43. LIGO/Virgo/KAGRA S240716b: Updated Sky localization
  44. GRB 240713A: Swift-XRT observations
  45. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  46. SVOM/GRM In-Flight Trigger of GRB 240715A
  47. GRB 240713A: LAST optical upper limit
  48. LIGO/Virgo/KAGRA S240716b: Identification of a GW compact binary merger candidate
  49. GRB 240715A: Swift ToO observations
  50. Fermi GRB 240715A: Global MASTER-Net observations report
  51. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  52. GRB 240715A: Fermi GBM Observation
  53. GRB 240712A ATCA radio observations
  54. GRB240715A: GRANDMA Optical Upper Limits
  55. IPN triangulation of GRB 240715A (short)
  56. GRB 240712A: Swift/UVOT Upper Limits
  57. EP-WXT flaring star and the optical flaring activity during its decay phase
  58. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  59. GRB 240713A: Tiled Swift observations
  60. GRB 240713A: J-band upper limit from WINTER
  61. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  62. GRB 240713A: JinShan optical upper limits
  63. GRB 240713A: OHP/T120 optical upper limit
  64. GRB240713A: X-ray follow-up observation with EP-FXT (duplicate submission of GCN 36859)
  65. GRB240713A: X-ray follow-up observation with EP-FXT
  66. GRB240713A: Optical upper limit with Kinder observations
  67. Fermi Sub-threshold Observation of GRB240713A
  68. EP240708a: GSP optical upper limit
  69. LIGO/Virgo/KAGRA S240627by: Updated Sky localization and EM Bright Classification
  70. EP240708a: KAIT optical upper limit
  71. Fermi GRB 240710A: Global MASTER-Net observations report
  72. EP240708a: NOT optical observations
  73. EP240708a: SVOM/C-GFT optical upper limit
  74. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  75. EP240708a: Optical upper limits with Kinder observations
  76. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  77. EP240703b: GSP optical upper limit
  78. EP240703b: TRT optical upper limits
  79. EP240703a: TRT further optical observation
  80. EP240702a: TRT optical upper limits
  81. Konus-Wind detection of GRB 240627A
  82. LIGO/Virgo/KAGRA S240705at: Updated Sky localization
  83. EP240703a and EP240703b: Swift/XRT upper limits
  84. LIGO/Virgo/KAGRA S240705at: Identification of a GW compact binary merger candidate
  85. EP240703a: KAIT optical upper limit
  86. EP240703a: BTA observations
  87. EP240703c: Kinder optical follow-up and Swift XRT observations
  88. EP240703a: Liverpool Telescope optical follow-up observations
  89. EP240703a/GRB 240703A: TRT optical candidate likely not real
  90. EP240703a: Kinder optical follow-up observations
  91. LIGO/Virgo/KAGRA S240703ad: Updated Sky localization
  92. LIGO/Virgo/KAGRA S240703ad: Identification of a GW compact binary merger candidate
  93. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  94. IPN triangulation of GRB 240627A
  95. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  96. LIGO/Virgo/KAGRA S240422ed: Updated significance estimate
  97. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  98. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  99. EP240702a: Swift/XRT upper limit
  100. EP240702a: GSP optical upper limit

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