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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"

32501 results found.

  1. GRB 030329 Optical Observations
  2. GRB030328, optical observation
  3. GRB 030329, BVRI photometry
  4. GRB030429: Optical Observations
  5. GRB030501: TAROT candidate afterglow present in archival images
  6. GRB 030501: TAROT possible candidate counterpart
  7. IPN triangulation of GRB030501 (IBIS event; annulus)
  8. GRB 030429: confirmation of afterglow candidate
  9. GRB030425: CrAO optical observation
  10. GRB 030329 Oprical observations in Rozhen observatory
  11. GRB 030324: Radio Observations
  12. GRB030329 observed as a sudden ionospheric disturbance (SID)
  13. GRB030329, SPM optical observations
  14. GRB 030329, the review of the sky area in plate archive (1950-1998)
  15. GRB 030329: Spectral Evolution of SN 2003dh
  16. GRB 030329: optical spectropolarimetry at VLT
  17. GRB030329: optical polarization
  18. GRB030329, optical observation
  19. GRB030329: 444 AAVSO Measurements
  20. ROTSE-III prompt optical detections of GRB 030418
  21. GRB030418: Upper limits from recent and historical observations.
  22. GRB 030418: Optical afterglow
  23. GRB 030418: Finder for afterglow candidate
  24. GRB 030329 OT position
  25. GRB030329: Optical Observations
  26. OT GRB 030329: early UBVRcIc spectral evolution
  27. GRB030329, UBVRI polarimetry, R-polarization
  28. GRB 030329: SARA Optical Observations
  29. OT GRB 030329: early spectrum
  30. GRB030329: VR Photometry at TNG
  31. GRB030324: Candidate Optical Afterglow
  32. GRB 030413: Optical Observations
  33. GRB 030329 Rc observations
  34. Superluminal motion in GRB 030329 (Correction)
  35. Superluminal motion in GRB 030329
  36. GRB 030329 and SN 2003dh
  37. GRB030329, optical position
  38. GRB 030329 VLBA Observations
  39. GRB 030329: BVRI photometry at Asiago
  40. GRB 030329, light curve flattens
  41. GRB 030329: VLT V-band photometry
  42. If the SN/GRB connection confirmed
  43. GRB 030329: Supernova Confirmed
  44. GRB030329: RTT150 optical observations
  45. GRB030329: Near Infrared Observations at Gunma
  46. GRB030329: HET spectroscopic monitoring
  47. GRB 030329, color evolution
  48. GRB030328, UBVRcIc field photometry
  49. GRB030329: Optical observcations
  50. GRB030329: BV photographic observations
  51. GRB 030329 Optical observations
  52. GRB 030329, color evolution
  53. GRB 030329: possible color change
  54. GRB030329: RTT150 optical observations
  55. GRB 030329: Supernova Spectrum Emerging
  56. GRB030329: RTT150 optical observation
  57. GRB030329: More AAVSO VR obs
  58. GRB030328: R upper limit after 6 hours by MASTER
  59. GRB 030329: BV photographic observations
  60. GRB 030329: SARA Optical Observations
  61. GRB 030329: SARA Optical Observations
  62. GRB030329, fading resumes
  63. GRB 030329, BVRI photometry
  64. GRB030329: Optical observations
  65. SDSS 0.5m PT observations of GRB030329 (correction)
  66. SDSS 0.5m PT observations of GRB030329
  67. GRB 030329, Optical observations
  68. GRB 030329, nearby galaxies
  69. GRB030329, cessation of fading
  70. GRB030329: final R-band light curve by MASTER
  71. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  72. GRB 030329: Sub-millimeter detection
  73. GRB 030329: SARA Optical Observations
  74. GRB 030329: SARA Optical Observations
  75. OT GRB light curves and SN predictions
  76. GRB030329, optical observation
  77. GRB030329, optical observation
  78. GRB030329, new UBVRcIc field photometry
  79. GRB 030329, light curve and SN prediction
  80. GRB030329: optical observations at Tokyo Tech
  81. GRB 030329: optical observations
  82. GRB030329: multiple re-brightening phases
  83. GRB 030329, BRI photometry
  84. GRB030329: Optical observations at Teramo
  85. GRB030329: more 15GHz observations
  86. Further AAVSO V,B,R observations of GRB030329
  87. GRB 030329: Additional Mt. Laguna Optical Observations
  88. GRB 030329: SARA Optical Observations
  89. GRB 030329: Observations with ANDICAM
  90. GRB030329: Optical observations
  91. GRB 030329: Correction to GCN 2056
  92. GRB 030329: fitting parameters and re-brightening
  93. GRB 030329: KAIT optical photometry
  94. GRB030329 Further RBO Optical Observations
  95. triangulation of GRB 030331 (single error box)
  96. GRB030329 - OT rebrightens
  97. GRB 030329: SARA Optical Observations
  98. AAVSO V & R observations of GRB030329
  99. GRB 030329: optical observations
  100. IPN triangulation of GRB030329b (large error box)

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