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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').
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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"

5545 results found.

  1. Fermi GRB 241207A: Global MASTER-Net observations report
  2. Fermi GRB 241206A: Global MASTER-Net observations report
  3. Fermi GRB 241204A: Global MASTER-Net observations report
  4. EP241201a: Global MASTER-Net observations report
  5. Fermi GRB 241201A: Global MASTER-Net observations report
  6. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  7. GRB 241127A: Swift detection of a burst with an optical counterpart
  8. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  9. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  10. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  11. IPN triangulation of GRB 241117A
  12. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  13. Fermi GRB 241118A: Global MASTER-Net observations report
  14. Fermi GRB 241117A: Global MASTER-Net observations report
  15. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  16. EP241113a: No Detection in Fermi-GBM Observations
  17. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  18. EP241113a: Global MASTER-Net observations report
  19. EP241113b: Global MASTER-Net observations report
  20. EP241113a: EP on-board trigger and autonomous follow-up observation
  21. GRB 241113A: LCO optical observations
  22. GRB241113A: LCOGT (40-cm) optical counterpart detection
  23. Fermi trigger No 753166198: Global MASTER-Net observations report
  24. GRB 241112B: AbAO optical upper limit
  25. Fermi GRB 241112A: Global MASTER-Net observations report
  26. GRB 241112B: Swift-XRT afterglow detection
  27. GRB 241112B: SVOM/VT afterglow detection
  28. EP241107a: EP-FXT follow-up observations
  29. GRB 241025C: VZLUSAT-2 detection
  30. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  31. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  32. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  33. Fermi trigger No 752878030: Global MASTER-Net observations report
  34. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  35. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  36. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  37. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  38. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  39. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  40. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  41. GRB 240511A: LCO upper limits
  42. Fermi GRB 241105A: Global MASTER-Net observations report
  43. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  44. EP241103a: Global MASTER-Net observations report
  45. EP241101a: Global MASTER-Net observations report
  46. Fermi trigger No 752083996: Global MASTER-Net observations report
  47. GRB 241029A: LCO optical detection
  48. Fermi trigger No 752006065: Global MASTER-Net observations report
  49. EP241021a: Swift-UVOT detection
  50. EP241021a: Optical rebrightening observations with Mephisto
  51. GRB 241030A : MITSuME Akeno optical afterglow detection
  52. GRB 241029A: GOTO optical afterglow detection
  53. GRB 241029A: MASTER early optical counterpart detection
  54. GRB 241029A: TRT optical afterglow candidate detection
  55. EP 241026b: LBT optical observations
  56. GRB 241026A: SAO RAS observations of possible optical afterglow
  57. Fermi trigger No 751554401: Global MASTER-Net observations report
  58. Fermi trigger No 751449953: Global MASTER-Net observations report
  59. EP241021a: TRT optical observations
  60. GRB 241009A: LCO optical upper limits
  61. GRB 241006A: ATCA Radio Upper Limits
  62. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  63. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  65. Fermi GRB 241008A: Global MASTER-Net observations report
  66. IceCube-241006A: No candidates from the Zwicky Transient Facility
  67. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  68. GRB 240910A: LBT optical observations
  69. Fermi trigger No 749721670: Global MASTER-Net observations report
  70. GRB 240930B / EP 240930a: SVOM/GRM observation
  71. Fermi trigger No 749735279: Global MASTER-Net observations report
  72. Fermi trigger No 749630753: Global MASTER-Net observations report
  73. Fermi trigger No 749693019: Global MASTER-Net observations report
  74. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  75. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  76. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  77. NuEm-240926A: Upper limits from a search for coincident neutrino events in IceCube
  78. GRB 241002B: GOTO optical counterpart candidate
  79. GRB 240930B: GRBAlpha detection
  80. GRB 240929A: GRBAlpha detection
  81. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  82. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  83. EP240930a: GOTO optical upper limits
  84. GRB 240929A: SVOM/GRM observation
  85. EP EP240930a: Global MASTER-Net observations report
  86. EP240930a: EP-WXT detection of a fast X-ray transient
  87. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  88. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  89. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  90. AMON NuEM 240926A: Swift XRT Follow-up
  91. GRB 240929A : Leavitt Observatory optical upper limit
  92. Fermi GRB 240930B: Global MASTER-Net observations report
  93. GRB 240825A: LBT optical observations
  94. GRB 240928A: SVOM/GRM observation
  95. Fermi GRB 240930A: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  97. Fermi trigger No 749339671: Global MASTER-Net observations report
  98. Fermi GRB 240929A: Global MASTER-Net observations report
  99. Integral GRB240929.83: Global MASTER-Net observations report
  100. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event

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