ER UMa has changed its outburst property?

(vsnet-alert 718)

Following observations extracted from vsnet-obs reports seem to indicate ER UMa never faded to its quiescence in January. The light curve in late Januanry to early February looks like a standstill or an extended superoutburst accompanied by a brightening around Feb. 1. Previous superoutbursts of ER UMa usually last 19 days (with a very regular duty cycle ~0.4 to its supercycle 43 days). Has its outburst property changed? Please keep a close eye on this particuliar dwarf nova, the best known and the brightest member among its allies (ER UMa stars or RZ LMi stars -- cf. http://www.kusastro.kyoto-u.ac.jp/vsnet/DNe/eruma.html).

    YYMMDD(UT)   mag  code
    970101.051   133  POY
    970101.938   135  POY
    970103.051   138  POY
    970103.892   125  JEN
    970106.866   125  JEN
    970107.869   124  PIE
    970109.633   126  Wnt
    970109.947   131  JEN
    970111.849   130  PIE
    970111.948   130  JEN
    970112.605  13.27V  Oud
    970113.594  13.25V  Oud
    970113.840   132  PIE
    970114.900   132  PIE
    970114.965   135  POY
    970114.994   127  JEN
    970115.633  13.43V  Oud
    970115.869   131  PIE
    970116.830   133  PIE
    970117.783   136  Wnt
    970117.901   135  POY
    970117.926   138  JEN
    970119.871  13.55V  Oud
    970125.842   137  POY
    970126.792   135  BMU
    970126.817   137  POY
    970128.849   135  POY
    970131.773   132  Wnt
    970201.780   130  PIE
    970201.797   135  JEN
    970201.823  13.35V  Oud
    970201.887   135  BMU
    970202.917   135  POY
    970203.646   135  Wnt
    970205.960   142  PIE
    970206.860   151: PIE
    970207.860   148  POY

Regards,
Taichi Kato

ER UMa: superoutburst overdue

(vsnet-alert 749)

ER UMa

Observations reported to vsnet-obs indicate the superoutburst is apparently overdue since its last in January. This may be somehow associated with the possible unexpected duration of the January superoutburst (cf. vsnet-alert 718, http://www.kusastro.kyoto-u.ac.jp/vsnet/DNe/erumaob.html).

Observers are strongly urged to monitor closely this ER UMa-type prototype to see if any change of supercycle (formerly length = 43 days) happens.

  YYMMDD(UT)   mag  code
  970125.842   137  POY
  970126.792   135  BMU
  970126.817   137  POY
  970128.135  13.52  JEN
  970128.849   135  POY
  970131.773   132  Wnt
  970201.780   130  PIE
  970201.797   135  JEN
  970201.823  13.35V  Oud
  970201.887   135  BMU
  970202.917   135  POY
  970203.646   135  Wnt
  970205.960   142  PIE
  970206.860   151: PIE
  970207.860   148  POY
  970209.812   139  Wnt
  970211.156   149  POY
  970211.648  <139  Wnt
  970213.817   142  POY
  970218.701  <134  Wnt
  970218.869  <141  POY
  970219.607  <134  Wnt
  970221.715  <130  Wnt
  970221.822   132  POY

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