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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"

32509 results found.

  1. GRB030501, optical observation
  2. GRB030501 observation report
  3. GRB030501 triangulation (correction to GCN 2194)
  4. GRB030329: RTT150 optical observations and upper limit for a host
  5. GRB 030429: Radio Observations
  6. GRB 030429: redshift from VLT spectroscopy
  7. GRB 030429: IR photometry with IRSF/SIRIUS
  8. GRB030501B triangulation (single error box)
  9. GRB 030329 Optical Observations
  10. GRB030328, optical observation
  11. GRB 030329, BVRI photometry
  12. GRB030429: Optical Observations
  13. GRB030501: TAROT candidate afterglow present in archival images
  14. GRB 030501: TAROT possible candidate counterpart
  15. IPN triangulation of GRB030501 (IBIS event; annulus)
  16. GRB 030429: confirmation of afterglow candidate
  17. GRB030425: CrAO optical observation
  18. GRB 030329 Oprical observations in Rozhen observatory
  19. GRB 030324: Radio Observations
  20. GRB030329 observed as a sudden ionospheric disturbance (SID)
  21. GRB030329, SPM optical observations
  22. GRB 030329, the review of the sky area in plate archive (1950-1998)
  23. GRB 030329: Spectral Evolution of SN 2003dh
  24. GRB 030329: optical spectropolarimetry at VLT
  25. GRB030329: optical polarization
  26. GRB030329, optical observation
  27. GRB030329: 444 AAVSO Measurements
  28. ROTSE-III prompt optical detections of GRB 030418
  29. GRB030418: Upper limits from recent and historical observations.
  30. GRB 030418: Optical afterglow
  31. GRB 030418: Finder for afterglow candidate
  32. GRB 030329 OT position
  33. GRB030329: Optical Observations
  34. OT GRB 030329: early UBVRcIc spectral evolution
  35. GRB030329, UBVRI polarimetry, R-polarization
  36. GRB 030329: SARA Optical Observations
  37. OT GRB 030329: early spectrum
  38. GRB030329: VR Photometry at TNG
  39. GRB030324: Candidate Optical Afterglow
  40. GRB 030413: Optical Observations
  41. GRB 030329 Rc observations
  42. Superluminal motion in GRB 030329 (Correction)
  43. Superluminal motion in GRB 030329
  44. GRB 030329 and SN 2003dh
  45. GRB030329, optical position
  46. GRB 030329 VLBA Observations
  47. GRB 030329: BVRI photometry at Asiago
  48. GRB 030329, light curve flattens
  49. GRB 030329: VLT V-band photometry
  50. If the SN/GRB connection confirmed
  51. GRB 030329: Supernova Confirmed
  52. GRB030329: RTT150 optical observations
  53. GRB030329: Near Infrared Observations at Gunma
  54. GRB030329: HET spectroscopic monitoring
  55. GRB 030329, color evolution
  56. GRB030328, UBVRcIc field photometry
  57. GRB030329: Optical observcations
  58. GRB030329: BV photographic observations
  59. GRB 030329 Optical observations
  60. GRB 030329, color evolution
  61. GRB 030329: possible color change
  62. GRB030329: RTT150 optical observations
  63. GRB 030329: Supernova Spectrum Emerging
  64. GRB030329: RTT150 optical observation
  65. GRB030329: More AAVSO VR obs
  66. GRB030328: R upper limit after 6 hours by MASTER
  67. GRB 030329: BV photographic observations
  68. GRB 030329: SARA Optical Observations
  69. GRB 030329: SARA Optical Observations
  70. GRB030329, fading resumes
  71. GRB 030329, BVRI photometry
  72. GRB030329: Optical observations
  73. SDSS 0.5m PT observations of GRB030329 (correction)
  74. SDSS 0.5m PT observations of GRB030329
  75. GRB 030329, Optical observations
  76. GRB 030329, nearby galaxies
  77. GRB030329, cessation of fading
  78. GRB030329: final R-band light curve by MASTER
  79. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  80. GRB 030329: Sub-millimeter detection
  81. GRB 030329: SARA Optical Observations
  82. GRB 030329: SARA Optical Observations
  83. OT GRB light curves and SN predictions
  84. GRB030329, optical observation
  85. GRB030329, optical observation
  86. GRB030329, new UBVRcIc field photometry
  87. GRB 030329, light curve and SN prediction
  88. GRB030329: optical observations at Tokyo Tech
  89. GRB 030329: optical observations
  90. GRB030329: multiple re-brightening phases
  91. GRB 030329, BRI photometry
  92. GRB030329: Optical observations at Teramo
  93. GRB030329: more 15GHz observations
  94. Further AAVSO V,B,R observations of GRB030329
  95. GRB 030329: Additional Mt. Laguna Optical Observations
  96. GRB 030329: SARA Optical Observations
  97. GRB 030329: Observations with ANDICAM
  98. GRB030329: Optical observations
  99. GRB 030329: Correction to GCN 2056
  100. GRB 030329: fitting parameters and re-brightening

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