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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"

24573 results found.

  1. LIGO/Virgo S230611be: Global MASTER-Net observations report
  2. LIGO/Virgo S230611l: Global MASTER-Net observations report
  3. LIGO/Virgo/KAGRA S230609u: Updated Sky localization
  4. LIGO/Virgo S230609u: Global MASTER-Net observations report
  5. LIGO/Virgo S230608aw: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S230609u: Identification of a GW compact binary merger candidate
  7. LIGO/Virgo S230608as: Global MASTER-Net observations report
  8. LIGO/Virgo S230609a: Global MASTER-Net observations report
  9. LIGO/Virgo S230608ah: Global MASTER-Net observations report
  10. LIGO/Virgo S230608q: Global MASTER-Net observations report
  11. ZTF23aamxeqf/AT2023jxk: 1.3m DFOT Optical upper limit
  12. LIGO/Virgo/KAGRA S230608as: Identification of a GW compact binary merger candidate
  13. Fermi GRB 230603A: Global MASTER-Net observations report
  14. Fermi trigger No 707039690: Global MASTER-Net observations report
  15. GRB 230506B: Chandra localization of the X-ray afterglow
  16. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  17. GRB 230606A: Swift-BAT refined analysis
  18. GRB 230606A: Fermi GBM Observation
  19. LIGO/Virgo/KAGRA S230602ap: Zwicky Transient Facility observations
  20. GRB 230604A: GRBAlpha detection
  21. LIGO/Virgo S230606z: Global MASTER-Net observations report
  22. LIGO/Virgo S230606d: Global MASTER-Net observations report
  23. LIGO/Virgo/KAGRA S230606d: Identification of a GW compact binary merger candidate
  24. GRB 230606A: Swift detection of a burst
  25. Fermi-LAT gamma-ray observations of IceCube-230603A
  26. LIGO/Virgo/KAGRA S230605o: Updated Sky localization
  27. IceCube-230603A: Upper limits from a search for additional neutrino events in IceCube
  28. LIGO/Virgo/KAGRA S230601bf: Updated Sky localization
  29. Super-Kamiokande: Neutrino search for SN2023ixf
  30. LIGO/Virgo/KAGRA S230605o: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo S230605o: Global MASTER-Net observations report
  32. LIGO/Virgo S230604z: Global MASTER-Net observations report
  33. IceCube-230603A - IceCube observation of a high-energy neutrino candidate track-like event
  34. GRB 230603A: Fermi GBM Final Real-time Localization
  35. LIGO/Virgo S230603aa: Global MASTER-Net observations report
  36. LIGO/Virgo S230602ap: Global MASTER-Net observations report
  37. LIGO/Virgo/KAGRA S230518h: Upper limits from a two-week IceCube neutrino search
  38. GRB 230521A: VZLUSAT-2 detection
  39. GRB 230522A: GRBAlpha and VZLUSAT-2 joint detection
  40. LIGO/Virgo S230601bf: Global MASTER-Net observations report
  41. LIGO/Virgo/KAGRA S230601bf: Identification of a GW compact binary merger candidate
  42. LIGO/Virgo S230531f: Global MASTER-Net observations report
  43. GRB 230525A: CALET Gamma-Ray Burst Monitor detection
  44. LIGO/Virgo/KAGRA S230529ay: Zwicky Transient Facility observations
  45. LIGO/Virgo/KAGRA S230528a: Zwicky Transient Facility observations
  46. LIGO/Virgo/KAGRA S230527ch: Zwicky Transient Facility observations
  47. LIGO/Virgo/KAGRA S230529ay: Upper limits from CALET observations.
  48. LIGO/Virgo/KAGRA S230529ay: AstroSat CZTI non-detection and upper limits
  49. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  50. LIGO/Virgo/KAGRA S230529ay: upper limits from AGILE/MCAL
  51. LIGO/Virgo/KAGRA S230529ay: Coverage and upper limits from MAXI/GSC observations
  52. LIGO/Virgo/KAGRA S230529ay: Upper limits from Fermi-GBM Observations
  53. LIGO/Virgo/KAGRA S230529ay: Updated Sky localization and EM Bright Classification
  54. LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  55. LIGO/Virgo/KAGRA S230529ay: Identification of a GW compact binary merger candidate
  56. LIGO/Virgo S230529p: Global MASTER-Net observations report
  57. GRB 230529A: Fermi GBM Final Real-time Localization
  58. Alert from the HAWC Burst Monitor HAWC-230527A
  59. LIGO/Virgo S230525a: Global MASTER-Net observations report
  60. LIGO/Virgo/KAGRA S230518h: Updated Sky localization
  61. LIGO/Virgo/KAGRA S230520ae: Updated Sky localization
  62. Fermi-LAT gamma-ray observations of IceCube-230524A
  63. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  64. GRB 230510A: Swift-BAT refined analysis
  65. GRB 230525A: Fermi GBM Detection
  66. LIGO/Virgo/KAGRA S230518h: TESS observations of the localization region
  67. GRB 230525A: Fermi GBM Final Localization
  68. IceCube-230524A: Upper limits from a search for additional neutrino events in IceCube
  69. GRB 230523B: GRBAlpha detection
  70. GRB 230524A: Fermi GBM Observation
  71. IceCube Alert 230524.47: Global MASTER-Net observations report
  72. LIGO/Virgo/KAGRA S230518h: No transient candidates in CALET observations
  73. LIGO/Virgo/KAGRA S230524x: Retraction of GW compact binary merger candidate
  74. IceCube-230524A - IceCube observation of a high-energy neutrino candidate track-like event
  75. Fermi trigger No 706610076: Global MASTER-Net observations report
  76. LIGO/Virgo S230524b: Global MASTER-Net observations report
  77. GRB 230524A: Fermi GBM Final Real-time Localization
  78. Fermi trigger No 706599831: Global MASTER-Net observations report
  79. Fermi trigger No 706536788: Global MASTER-Net observations report
  80. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  81. LIGO/Virgo/KAGRA S230521k: Additional candidates from Zwicky Transient Facility
  82. GRB 230523A: Fermi GBM Final Real-time Localization
  83. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230523A
  84. LIGO/Virgo S230522n: Global MASTER-Net observations report
  85. LIGO/Virgo S230522a: Global MASTER-Net observations report
  86. LIGO/Virgo/KAGRA S230522n: Upper limits from IceCube neutrino search
  87. LIGO/Virgo/KAGRA S230522a: 2 counterpart neutrino candidates from IceCube neutrino searches
  88. LIGO/Virgo S230521k: Global MASTER-Net observations report
  89. LIGO/Virgo/KAGRA S230521k: Zwicky Transient Facility observations
  90. GRB 230518B: VZLUSAT-2 detection
  91. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  92. Fermi trigger No 706328428: Global MASTER-Net observations report
  93. IPN triangulation of GRB 230518A (short)
  94. Fermi trigger No 706331483: Global MASTER-Net observations report
  95. Fermi trigger No 706317104: Global MASTER-Net observations report
  96. GRB 230521A: Fermi GBM Final Real-time Localization
  97. LIGO/Virgo/KAGRA S230520ae: Identification of a GW compact binary merger candidate: End-to-End Test
  98. GRB 230520B: Fermi GBM Final Real-time Localization
  99. LIGO/Virgo/KAGRA S230520ae: Upper limits from IceCube neutrino search
  100. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet

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