The Relative Orientation between Local Magnetic Field and Galactic Plane in Low Latitude Dark Clouds

作     者：Gulafsha B.Choudhury Himadri S.Das B.J.Medhi J.C.Pandey S.Wolf T.K.Dhar A.M.Mazarbhuiya Gulafsha B.Choudhury;Himadri S.Das;B.J.Medhi;J.C.Pandey;S.Wolf;T.K.Dhar;A.M.Mazarbhuiya

作者机构：Department of PhysicsAssam UniversitySilchar 788011India Department of PhysicsGauhati UniversityGuwahati 781014India Aryabhatta Research Institute of Observational Sciences(ARIES)Nainital 263002India University of KielInstitute of Theoretical Physics and AstrophysicsLeibnizstrasse 15D-24118KielGermany 

出 版 物：《Research in Astronomy and Astrophysics》 (天文和天体物理学研究（英文版）)

年 卷 期：2022年第22卷第7期

页      面：84-98页

核心收录：

学科分类：07[理学] 070401[理学-天体物理] 0704[理学-天文学] 

基　　金：funding agency Department of Science and Technology (DST)  Government of India for providing the DST INSPIRE fellowship (IF 170830) 

主　　题：polarization (ISM:)dust extinction ISM:magnetic fields galaxies:magnetic fields 

摘      要：In this work,we study the magnetic field morphology of selected star-forming clouds spread over the galactic latitude(b)range−10°to 10°.The polarimetric observations of clouds CB24,CB27 and CB188 are conducted to study the magnetic field geometry of those clouds using the 104 cm Sampurnanand Telescope(ST)located at ARIES,Manora Peak,Nainital,*** observations are combined with those of 14 further low latitude clouds available in the *** of these clouds are located within a distance range 140–500 pc except for CB3(∼2500 pc),CB34(∼1500 pc),CB39(∼1500 pc)and CB60(∼1500 pc).Analyzing the polarimetric data of 17 clouds,we find that the alignment between the envelope magnetic field(θ^(env)_(B))and galactic plane(GP)(θGP)of the low-latitude clouds varies with their galactic longitudes(l).We observe a strong correlation between the longitude(l)and the offset(θ_(off)=|θ^(env)_(B)-θ_(GP))which shows that θ^(env)_(B) is parallel to the GP when the clouds are situated in the region 115°250°.To check the consistency of our results,the stellar polarization data available in the Heiles catalog are overlaid on the DSS image of the clouds having mean polarization vector of field *** results are almost consistent with the Heiles data.A systematic discussion is presented in the *** effect of turbulence in the cloud is also studied which may play an important role in causing the misalignment phenomenon observed between θ^(env)_(B) and θ_(GP).We have used Herschel(Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.)SPIRE 500μm and SCUBA 850μm dust continuum emission maps in our work to understand the density structure of the clouds.