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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"

4930 results found.

  1. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  2. GRB 030329: SARA Optical Observations
  3. GRB 030329, BRI photometry
  4. Further AAVSO V,B,R observations of GRB030329
  5. GRB 030329: SARA Optical Observations
  6. GRB 030329: Observations with ANDICAM
  7. GRB030329: further optical photometry and evidence for a light curve discontinuity
  8. GRB 030329: Correction to GCN 2056
  9. AAVSO V & R observations of GRB030329
  10. GRB 030329: optical observations
  11. GRB030329 15 GHz radio observation
  12. 030331 NOT A GRB
  13. GRB030329: R and B observations
  14. GRB030329, SPM optical observations
  15. GRB 030329: Optical Decay
  16. GRB030329: optical spectroscopy with the TNG
  17. GRB 030328 Optical Observations
  18. GRB030328: Decay index
  19. GRB030323 optical observations
  20. GRB030323: Detection on 2003/03/24
  21. GRB 030323: SARA Optical Observations
  22. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  23. GRB 030227: Optical limit at RIKEN
  24. GRB 030226 Optical observations
  25. Chandra detection of the X-ray afterglow of GRB 030226
  26. GRB030227: Kiso optical upper limit
  27. 030302: NOT A GRB
  28. Possible break in the GRB 030226 light curve
  29. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  30. GRB 030226 simultaneous optical observations
  31. GRB030226: Optical decay index
  32. GRB030131: Candidate Optical Afterglow
  33. GRB 030131: afterglow candidate
  34. GRB 030115, simultaneous observations by BOOTES-1
  35. GRB 030115: Radio Observations
  36. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  37. GRB 030115, optical candidate
  38. Possible GRB030113 seen by SPI ACS
  39. Probable GRB030112B seen by SPI ACS
  40. Probable GRB030112 seen by SPI ACS
  41. Possible GRB030111 seen by SPI ACS
  42. Possible GRB030110b seen by SPI ACS
  43. Possible GRB 030110 seen by SPI ACS
  44. GRB021112 (=H2448): A Long GRB Localized by HETE
  45. GRB021104: possible optical afterglow
  46. GRB021016, optical observations
  47. GRB021004: Optical Observations
  48. GRB021004: BVRc photometry
  49. GRB021004 radio observation
  50. GRB 021004: Optical Decay
  51. GRB 021004: Optical Observations
  52. GRB 021004: Optical Observations
  53. GRB 021004, optical observations
  54. GRB 021004 radio search
  55. INTEGRAL GRBs added to GCN
  56. GRB 020812: early time optical observation at Ouda Station
  57. Early Time Limits for GRB020813
  58. GRB 020813 Afterglow Observations; Possible break
  59. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  60. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  61. IPN triangulation of GRB020714
  62. IPN triangulation of GRB020714
  63. GRB 020625, optical observations
  64. AXP 1E2259+586 optical observations
  65. IPN detection of possible bursts from SGR1806-20
  66. GRB 020409: No Evidence for an Optical Afterglow
  67. GRB020331 optical observations with RIMOTS
  68. Short RXTE/ASM transient 020406; may be a GRB
  69. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  70. GRB011212: Optical Observations
  71. Bepposax GRB020322 The second springtime BSAX GRB
  72. GRB 020317 : KISO Optical Observations
  73. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  74. GRB020127 Optical Observations
  75. GRB011212: Optical observations at Gunma
  76. GRB 011211, Optical Observations
  77. GRB 011130: Optical Observations of Chandra Sources
  78. GRB 011130 I-band Observation
  79. GRB011130 (XRF011130) SDSS PT i-band observations
  80. XRF011130: Infrared Observations
  81. GRB011130, Radio Observations
  82. GRB010921, optical observation
  83. GRB010921 Optical Observations
  84. SGR1900+14 burst seen by HETE: BeppoSAX data
  85. GRB 010629 Optical Observations
  86. SGR1900+14: High Fluence Burst Localized by HETE
  87. GRB010326: Localization by HETE
  88. Sub-millimeter Excess/GRB 010222
  89. GRB010222: Sub-millimeter detection
  90. GRB010214 Optical Observation
  91. CORRECTION to XMM-Newton observation of GRB001025
  92. XMM-Newton observation of GRB001025
  93. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  94. ASM Localization of GRB 001025
  95. GRB 001007, BVR-band observations
  96. GRB000926 - Amateur Optical Observations
  97. GRB000926 optical observations
  98. GRB 000615, near-infrared observations
  99. IPN triangulation of GRB000516
  100. GRB 000418, Optical Observation

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