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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"

39220 results found.

  1. Fermi GRB 240718A: Global MASTER-Net observations report
  2. LAT GRB240718.27: Global MASTER-Net observations report
  3. GRB 240718A: Fermi GBM Observation
  4. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  5. GRB 240718A: Fermi-LAT Detection
  6. GRB 240718A: SVOM/GRM observation
  7. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  8. GRB 240718A: Fermi GBM Final Real-time Localization
  9. GRB 240712A: Swift-BAT refined analysis
  10. GRB 240716A: GECAM-B detection of a long burst
  11. SVOM/GRM In-Flight Trigger of GRB 240716A
  12. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  13. GRB 240713A: 2.2m CAHA optical limit
  14. GRB 240715A: Swift/UVOT observations of the XRT sources.
  15. GRB 240715A: Swift-XRT observations
  16. GRB240713A: Swift/UVOT Upper LImits
  17. GRB 240715A: GECAM-C detection of a short burst
  18. Konus-Wind detection of GRB 240715A
  19. GRB 240713A: Swift-XRT observations
  20. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  21. GRB 240712A: Swift-XRT refined Analysis
  22. SVOM/GRM In-Flight Trigger of GRB 240715A
  23. GRB 240713A: LAST optical upper limit
  24. GRB 240715A: Swift ToO observations
  25. Fermi GRB 240715A: Global MASTER-Net observations report
  26. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  27. GRB 240715A: Fermi GBM Observation
  28. GRB 240712A ATCA radio observations
  29. GRB240715A: GRANDMA Optical Upper Limits
  30. IPN triangulation of GRB 240715A (short)
  31. GRB 240712A: Swift/UVOT Upper Limits
  32. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  33. GRB 240715A: Fermi GBM Final Real-time Localization
  34. GRB 240713A: Tiled Swift observations
  35. GRB 240713A: J-band upper limit from WINTER
  36. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  37. GRB 240713A: JinShan optical upper limits
  38. GRB 240713A: OHP/T120 optical upper limit
  39. GRB240713A: X-ray follow-up observation with EP-FXT
  40. GRB 240713B: AstroSat CZTI detection of a long burst
  41. GRB240713A: Optical upper limit with Kinder observations
  42. Fermi Sub-threshold Observation of GRB240713A
  43. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  44. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  45. EP240708a: GSP optical upper limit
  46. GRB 240712A: Swift detection of a burst
  47. GRB 240711A: Fermi GBM Final Real-time Localization
  48. Fermi trigger No 742405878: Global MASTER-Net observations report
  49. Fermi trigger No 742317942: Global MASTER-Net observations report
  50. EP240708a: KAIT optical upper limit
  51. Fermi GRB 240710A: Global MASTER-Net observations report
  52. GRB 240710A: Fermi GBM Final Real-time Localization
  53. EP240708a: SVOM/C-GFT optical upper limit
  54. EP240703b: GSP optical upper limit
  55. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  56. GRB 240705A: Fermi GBM Final Real-time Localization
  57. EP240703b: TRT optical upper limits
  58. EP240703a: TRT further optical observation
  59. EP240702a: TRT optical upper limits
  60. Konus-Wind detection of GRB 240627A
  61. IPN triangulation of GRB 240628B (short)
  62. EP240703a: KAIT optical upper limit
  63. EP240703a: BTA observations
  64. EP240703a: Liverpool Telescope optical follow-up observations
  65. EP240703a/GRB 240703A: TRT optical candidate likely not real
  66. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  67. IPN triangulation of GRB 240627A
  68. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  69. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  70. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  71. EP240702a: GSP optical upper limit
  72. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  73. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  74. Fermi GRB 240702A: Global MASTER-Net observations report
  75. GRB 240702A: Fermi GBM Final Real-time Localization
  76. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  77. Fermi Gamma-ray Burst Monitor trigger 741448122/240630575 is not a GRB
  78. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  79. Fermi trigger No 741448122: Global MASTER-Net observations report
  80. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  81. Fermi trigger No 741356809: Global MASTER-Net observations report
  82. Fermi GRB 240629A: Global MASTER-Net observations report
  83. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB
  84. Fermi Gamma-ray Burst Monitor trigger 741288821/240628732 is not a GRB
  85. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  86. GRB 240629A: Fermi GBM Final Real-time Localization
  87. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  88. Fermi trigger No 741296200: Global MASTER-Net observations report
  89. Fermi trigger No 741251380: Global MASTER-Net observations report
  90. IPN triangulation of GRB 240619C
  91. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  92. GRB 240627A: NuSTAR Detection of the long GRB
  93. GRB 240615A: SAI CMO J- band observations
  94. GRB 240627A: AstroSat CZTI detection
  95. Fermi trigger No 741211696: Global MASTER-Net observations report
  96. EP240626a: Montarrenti Observatory optical upper limit
  97. EP240626a: KAIT optical upper limit
  98. GRB 240624A: Swift-BAT refined analysis
  99. Konus-Wind detection of GRB 240619A
  100. Fermi GRB 240625B: Global MASTER-Net observations report

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