Janet Preston, Denis Erkal, Michelle L. M. Collins, Rodrigo Ibata, R. Michael Rich
{"title":"M31 西北气流下段的特性","authors":"Janet Preston, Denis Erkal, Michelle L. M. Collins, Rodrigo Ibata, R. Michael Rich","doi":"arxiv-2409.07410","DOIUrl":null,"url":null,"abstract":"We present a kinematic and spectroscopic analysis of 40 red giant branch\nstars, in 9 fields, exquisitely delineating the lower segment of the North West\nStream (NW-K2), which extends for $\\sim$80 kpc from the centre of the Andromeda\ngalaxy. We measure the stream's systemic velocity as -439.3$^{+4.1}_{-3.8}$\nkm/s with a velocity dispersion = 16.4$^{+5.6}_{-3.8}$ km/s that is in keeping\nwith its progenitor being a dwarf galaxy. We find no detectable velocity\ngradient along the stream. We determine $-$1.3$\\pm$0.1 $\\le$ <[Fe/H]$_{\\rm\nspec}$> $\\le$ $-$1.2$\\pm$0.8 but find no metallicity gradient along the stream.\nWe are able to plausibly associate NW-K2 with the globular clusters PandAS-04,\nPandAS-09, PAndAS-10, PAndAS-11, PandAS-12 but not with PandAS-13 or PandAS-15\nwhich we find to be superimposed on the stream but not kinematically associated\nwith it.","PeriodicalId":501187,"journal":{"name":"arXiv - PHYS - Astrophysics of Galaxies","volume":"77 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Properties of the Lower Segment of M31's North West Stream\",\"authors\":\"Janet Preston, Denis Erkal, Michelle L. M. Collins, Rodrigo Ibata, R. Michael Rich\",\"doi\":\"arxiv-2409.07410\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We present a kinematic and spectroscopic analysis of 40 red giant branch\\nstars, in 9 fields, exquisitely delineating the lower segment of the North West\\nStream (NW-K2), which extends for $\\\\sim$80 kpc from the centre of the Andromeda\\ngalaxy. We measure the stream's systemic velocity as -439.3$^{+4.1}_{-3.8}$\\nkm/s with a velocity dispersion = 16.4$^{+5.6}_{-3.8}$ km/s that is in keeping\\nwith its progenitor being a dwarf galaxy. We find no detectable velocity\\ngradient along the stream. We determine $-$1.3$\\\\pm$0.1 $\\\\le$ <[Fe/H]$_{\\\\rm\\nspec}$> $\\\\le$ $-$1.2$\\\\pm$0.8 but find no metallicity gradient along the stream.\\nWe are able to plausibly associate NW-K2 with the globular clusters PandAS-04,\\nPandAS-09, PAndAS-10, PAndAS-11, PandAS-12 but not with PandAS-13 or PandAS-15\\nwhich we find to be superimposed on the stream but not kinematically associated\\nwith it.\",\"PeriodicalId\":501187,\"journal\":{\"name\":\"arXiv - PHYS - Astrophysics of Galaxies\",\"volume\":\"77 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-09-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - PHYS - Astrophysics of Galaxies\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2409.07410\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - PHYS - Astrophysics of Galaxies","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2409.07410","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Properties of the Lower Segment of M31's North West Stream
We present a kinematic and spectroscopic analysis of 40 red giant branch
stars, in 9 fields, exquisitely delineating the lower segment of the North West
Stream (NW-K2), which extends for $\sim$80 kpc from the centre of the Andromeda
galaxy. We measure the stream's systemic velocity as -439.3$^{+4.1}_{-3.8}$
km/s with a velocity dispersion = 16.4$^{+5.6}_{-3.8}$ km/s that is in keeping
with its progenitor being a dwarf galaxy. We find no detectable velocity
gradient along the stream. We determine $-$1.3$\pm$0.1 $\le$ <[Fe/H]$_{\rm
spec}$> $\le$ $-$1.2$\pm$0.8 but find no metallicity gradient along the stream.
We are able to plausibly associate NW-K2 with the globular clusters PandAS-04,
PandAS-09, PAndAS-10, PAndAS-11, PandAS-12 but not with PandAS-13 or PandAS-15
which we find to be superimposed on the stream but not kinematically associated
with it.