=========================== Available Spiral Arm Models =========================== The following table provides a summary of the spiral arm models included in **SpiralMap**. +------------------------+----------------------------------------------+ | **Model** | **Description** | +========================+==============================================+ | Taylor_Cordes_1992 | Model based on HII regions | +------------------------+----------------------------------------------+ | Vallee_1995 | Based on Galactic magnetic field/Dust/stars | +------------------------+----------------------------------------------+ | Drimmel_NIR_2000 | Based on Galactic plane emission in N | +------------------------+----------------------------------------------+ | Levine_2006 | Based on HI (21 cm) data | +------------------------+----------------------------------------------+ | Hou_Han_2014 | Logarithmic spiral using HII/GMC/Maser data | +------------------------+----------------------------------------------+ | Reid_2019 | MASER parallax model | +------------------------+----------------------------------------------+ | Poggio_cont_2021 | Map based on Upper Main Sequence stars | +------------------------+----------------------------------------------+ | GaiaPVP_cont_2022 | OB star map from Gaia Collaboration | +------------------------+----------------------------------------------+ | Drimmel_Ceph_2024 | Based on Cepheid variables | +------------------------+----------------------------------------------+ `Taylor_Cordes_1992` ----------------- * Class implementing the model from `Taylor & Cordes et al. 1993 `_ which is based on radio and optical observations of H II regions. * We use the model parameters presented in their Table 1. * There are four arms in this model (Arm1, Arm2, Arm3, Arm4). `Vallee_1995` ----------------- * Class implementing the model from `Vallee 1995 `_ which is based on Galactic magnetic field data, HI, HII, CO, and Dust. * We use their best model as depicted in their figure 3. * There are four arms in this model (Sagittarius, Scutum, Norma, Perseus). `Drimmel_NIR_2000` ----------------- * Class implementing the model from `Drimmel 2000 `_, which is based on Galactic plane emission profiles in the K band using COBE data. * Model publicly available. * There are two arms (1_arm, 2_arm) and two inter-arm regions (3_interarm, 4_interarm) in this model. `Levine_2006` ----------- * Class implementing the logarithmic spiral framework as described in `Levine et al. 2006 `_ based on HI observations. * Model taken from their Table 1. * There are four arms in this model (Arm1, Arm2, Arm3, Arm4). `Hou_Han_2014` ------------- * Class built upon the polynomial-logarithmic formulation introduced by `Hou et al. 2014 `_, based on a combination of H II, giant molecular clouds, and methanol MASER catalogs. * Model publicly available. * There are six arms in this model (Arm1, Arm2, Arm3, Arm4, Arm5, Arm6). * Additionally their local arm is included as a regular logarithmic spiral. `Reid_2019` --------- * Class implementing the model by `Reid et al. 2019 `_ based on radio astrometry of MASERS. * Model taken from their Table 2. * There are seven arms in this model (3-kpc, Norma, Sct-Cen, Sgr-Car, Local, Perseus, Outer). `Poggio_cont_2021` ------------- * Class used to extract the 2D contour maps of upper-main sequence stars by `Poggio et al. 2021 `_. The maps are based on Gaia EDR3 astrometry. * Data is available publicly, and also included in the package with their permission. `GaiaPVP_cont_2022` ------------- * Class used to extract the 2D contour maps of OB stars by `Gaia collaboration et al. 2022 `_. The maps are based on Gaia DR3 astrometry & astrophysical parameters. * Data is available publicly, and also included in the package with their permission. `Drimmel_Ceph_2024` ------------- * This class implements the model by `Drimmel et al. 2024 `_. It is based on a sample of 2857 dynamically young Milky Way Cepheids. * Model is publicly available but also included in the package as a userfriendly pickle file, with their permission. * There are four arms in this model (Scutum, Sag-Car, Orion, Perseus).