A photometric UBV survey is presented for 610 stars in a region surrounding the Cepheid AQ Puppis and centered southwest of the variable, based upon photoelectric measures for 14 stars and calibrated iris photometry of photographic plates of the field for 596 stars. An analysis of reddening and distance for program stars indicates that the major dust complex in this direction is ~1.8?kpc distant, producing differential extinction described by a ratio of total-to-selective extinction of R = AV /E B – V = 3.10 ± 0.20. Zero-age main-sequence fitting for the main group of B-type stars along the line of sight yields a distance of 3.21 ± 0.19?kpc (V 0 – MV = 12.53 ± 0.13?s.e.). The 2997 Cepheid AQ Pup, of field reddening E B – V = 0.47 ± 0.07 (E B – V (B0) = 0.51 ± 0.07), appears to be associated with B-type stars lying within 5' of it as well as with a sparse group of stars, designated Turner 14, centered south of it at J2000.0 = 07:58:37, –29:25:00, with a mean reddening of E B – V = 0.81 ± 0.01. AQ Pup has an inferred luminosity as a cluster member of MV = –5.40 ± 0.25 and an evolutionary age of 3 × 107 yr. Its observed rate of period increase of +300.1 ± 1.2 s yr–1 is an order of magnitude larger than what is observed for Cepheids of comparable period in the third crossing of the instability strip, and may be indicative of a high rate of mass loss or a putative fifth crossing. Another sparse cluster, designated Turner 13, surrounds the newly recognized 259 Cepheid V620 Pup, of space reddening E B – V = 0.64 ± 0.02 (E B – V (B0) = 0.68 ± 0.02), distance 2.88 ± 0.11?kpc (V 0 – MV = 12.30 ± 0.08?s.e.), evolutionary age 108 yr, and an inferred luminosity as a likely cluster member of MV = –2.74 ± 0.11. V620 Pup is tentatively identified as a first crosser, pending additional observations.
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机译：基于14个星的光电测量和596个星场的摄影版的校准虹膜光度法，提出了造父变星AQ Puppis周围且中心位于变星西南区域的610个星的光度UBV调查。对程序星的变红和距离的分析表明，该方向上主要的粉尘复合体距离〜1.8？kpc，产生了以总消灭与总消光之比为R = AV / EB – V = 3.10±的微分消光。 0.20。沿视线对主要B类恒星的零年龄主序列拟合产生的距离为3.21±0.19？kpc（V 0 – MV = 12.53±0.13？s.e。）。场变红EB – V = 0.47±0.07（EB – V（B0）= 0.51±0.07）的2997年造父变星AQ幼犬似乎与位于其5'内的B型恒星以及稀疏星有关一组名为Turner 14的恒星，位于它的南面，位于J2000.0 = 07：58：37，–29：25：00，平均EB变红– V = 0.81±0.01。 AQ Pup作为MV = –5.40±0.25的簇成员，具有推断的发光度，进化年龄为3×107年。其观测到的周期增加率+300.1±1.2 s yr–1比不稳定性带第三次穿越中可比周期的造父变星观测到的数量级大一个数量级，并且可能表明质量损失率很高或假定的第五次穿越。另一个稀疏的星团，称为特纳13，包围着新近认可的259个造父变星V620小狗，其空间变红EB – V = 0.64±0.02（EB – V（B0）= 0.68±0.02），距离为2.88±0.11？kpc（V 0 – MV = 12.30±0.08？se），进化年龄108岁，并且推断的光度可能是MV的群集成员= –2.74±0.11。暂定将V620幼犬确定为第一个过境者，有待进一步观察。
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