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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3383 results found.

  1. GRB 180914B: MASTER OT automatic dtection
  2. IceCube-180908A: CALET Gamma-Ray Burst Monitor upper limits
  3. GRB 180904A: BOOTES-2/TELMA early observations
  4. GRB 180904A: Swift detection of a burst
  5. GRB 180829A/MAXI J0406-019: MAXI/GSC detection
  6. GRB 180828A: Fermi GBM observation
  7. GRB 180818B: Fermi GBM observations
  8. Konus-Wind observation of GRB 180809B
  9. GRB 180809B: CALET Gamma-Ray Burst Monitor detection
  10. GRB 180809B: Swift detection of a burst with an optical afterglow
  11. GRB 180806.94: MASTER possible OT detection in Fermi GMB trigger 555287944 error box
  12. GRB 180805B: ESO/NTT optical observations
  13. GRB 180805B: Swift-BAT refined analysis (short GRB with extended emission)
  14. Fermi Trigger 554765006: MASTER optical inspection
  15. FRB 180725A: MASTER optical observations of the Fast Radio Burst error box
  16. GRB 180728B: Fermi GBM detection
  17. IPN Triangulation of GRB 180728B (short)
  18. GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
  19. GRB 180728A: Fermi GBM observation
  20. GRB 180728A: MASTER OT (= new object) detection
  21. GRB 180727A: Swift detection of a burst
  22. GRB 180718B: Swift-XRT observations
  23. GRB 180720B: MASTER Global Net OT observations
  24. GRB 180721A: MITSuME Akeno optical upper limits
  25. GRB 180722A: MAXI/GSC detection
  26. GRB 180720B: MAXI/GSC detection
  27. GRB 180720C: LT observations
  28. GRB 180715A: MASTER optical observation
  29. GRB 180715A: Swift detection of a short hard burst
  30. IceCube-171106A: MASTER optical observation
  31. GRB 180706A: Swift-BAT refined analysis
  32. GRB 180706A: Swift detection of a burst with optical counterpart
  33. Fermi GBM triggers 552488966/180705548 and 552490104/180705561 are not GRBs
  34. GRB 180630A: Swift/UVOT Detection
  35. GRB 180630A: Swift-BAT refined analysis
  36. GRB 180626C / Fermi trigger 551697835: MASTER inspection
  37. GRB 180630A: Enhanced Swift-XRT position
  38. GRB 180630A: Swift detection of a burst with an optical counterpart
  39. IPN Triangulation of GRB 180626C (short)
  40. IPN Triangulation of GRB 180529A (short/hard)
  41. GRB 180512A: VLT/HAWK-I NIR Observations
  42. IPN Triangulation of GRB 180427A
  43. GRB 180418A: TAROT La Silla observatory early optical observations
  44. GRB 180411A: CALET Gamma-Ray Burst Monitor detection
  45. GRB 180411A: Swift detection of a burst
  46. GRB 180410A: Swift detection of a burst or a Galactic transient.
  47. IPN Triangulation of GRB 180317A (short/hard)
  48. GRB 180316A: MITSuME Akeno optical upper limits
  49. GRB 180313A: Fermi GBM detection
  50. GRB 180314A: Fermi GBM observation
  51. GRB 180314A: Swift detection of a burst with an optical counterpart
  52. GRB 180311A: Swift detection of a burst
  53. IPN Triangulation of GRB 180223A (long)
  54. GRB 180205A: Mondy optical observations
  55. GRB180205A: Optical observations with DOAO 1m telescope
  56. GRB 180205A: Further GROND Observations reveal Afterglow is still bright
  57. GRB 180205A: Mondy optical observations
  58. GRB 180205A: Swift detection of a burst with a bright optical counterpart
  59. GRB 180113B: Fermi GBM detection
  60. GRB 180102A AROMA-N optical observation
  61. GRB 171216A: Swift detection of a burst
  62. GRB 171205A: ALMA observations
  63. GRB 171210A: Swift-XRT and UVOT observations
  64. GRB 171205A: Mondy optical observations
  65. GRB 171124A: TShAO optical observations
  66. INTEGRAL pointed follow-up of IceCube-171106A
  67. IPN Triangulation of GRB 171108A (short)
  68. GRB 171010A: afterglow and SN 2017htp optical observations
  69. GRB 171108A: Fermi GBM detection
  70. GRB 171030A: MASTER inspection of the IPN error box of the short GRB.
  71. Konus-Wind observation of GRB 171103A (short/hard)
  72. Konus-Wind observation of GRB 171102A
  73. Swift Triggers 784159 and 784160 are not bursts
  74. Swift Trigger 783893 is probably not a GRB
  75. Retraction of high energy neutrino candidate IceCube-171028
  76. GRB 171010A : Optical observations from HCT
  77. GRB 171010A: LCO 1m telescope observations
  78. GRB 171010A: OT, spectrum, and possible host galaxy
  79. LIGO/Virgo G298048/GW170817: updated localization from parameter estimation
  80. LIGO/Virgo G299232: MAGIC Cherenkov Telescopes observations
  81. LIGO/Virgo G299232: LOFAR follow-up
  82. GRB 171003A: Swift detection of a burst or a Galactic Transient
  83. GRB 171001A: Nanshan-0.36m optical afterglow detections
  84. GRB 171001A: Swift detection of a burst
  85. LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
  86. Correction to GCN Circular 21919: GRB 170921C: Insight-HXMT detection
  87. GRB 170921A: Swift detection of a burst
  88. LIGO/Virgo G298048: Desert Fireball Network simultaneous optical observations of the SSS17a/DLT17ck.
  89. LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
  90. LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
  91. GRB 170906A: Swift detection of a burst with an optical afterglow
  92. LIGO/Virgo G299232: Maidanak observations of optical transient SwiftJ014008.5+343403.6
  93. LIGO/Virgo G298048: e-MERLIN upper limits on 5 GHz compact emission from SSS17a
  94. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  95. LIGO/Virgo G298048: AGILE-GRID analysis of data contemporary to X-ray emission from SSS17a in NGC4993
  96. LIGO/Virgo G298048: Hubble Space Telescope observations
  97. LIGO/Virgo G298048: Possible Plateau in Ks band revealed by continued Gemini-South observations
  98. GRB 170830A: MAXI/GSC detection
  99. LIGO/Virgo G299232: observations of the optical Transient Discovered by Swift/UVOT
  100. LIGO/Virgo G299232: COATLI Observations of MASTER OT J033744.97+723159.0

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