GenISW: Simulated Integrated Sachs-Wolfe Maps

Maps of the Integrated Sachs-Wolfe and ancillary data are provided for the following N-body simulations: MICE Grand Challenge Lightcone Simulation <strong>File Structure</strong> <em>MICE_ISW_map_zmin_0.0_zmax_1.4_SBT_normal_nside_256.fits</em><br> Main ISW map for MICE in healpix format at nside=256 for constributions from z = 0 to 1.4 constructed from normal boundary spherical Bessel transforms. <em>MICE_alm_zmin_0.0_zmax_1.4_SBT_normal.txt</em><br> Alms for the above, to generate maps at the desired nside <em>MICE_Full.zip</em><br> ISW maps, alms and theory cls for MICE ISW for contribution from z = 0 to 1.4 <em>MICE_dz_02.zip</em><br> Same as above except these are divided into redshift bins of dz=0.2 <strong>Methods</strong> Spherical Bessel Transform with normal and derivative boundary conditions. Spherical Harmonic Scaling. Francis &amp; Peacock (2010) approximation. <strong>Data Products</strong> ISW maps in healpix format at nside=256 in units of K. ISW alms in units of K provided in ascii format Columns: real, imaginary. To generate HEALPix map with the desired nside: <pre><code class="language-python">import numpy as np import healpy as hp alm_fname = #provide name to alm file nside = #provide desired nside for map data = np.loadtxt(alm_fname, unpack=True) alm = data[0] + 1j*data[1] isw_map = hp.alm2map(alm, nside)</code></pre> Theoretical angular power spectra (Cls, which are provided unitless) with columns: l: spherical harmonic l modes. cl_ii: ISW auto-angular power spectra. cl_id: ISW-density cross-angular power spectra. cl_dd: Density auto-angular power spectra. cl_ii_limber: ISW auto-angular power spectra using the limber approximation. cl_id_limber`: ISW-density cross-angular power spectra using the limber approximation. cl_dd_limber: Density auto-angular power spectra using the limber approximation. Note: ISW maps and alms have already been multiplied by Tcmb = 2.7255. <strong>Citing</strong> Please cite the DOI for the zenodo repository. <strong>Contact</strong> Email: [e-mail]本数据集提供了以下N体模拟对应的积分萨克斯-沃尔夫（Integrated Sachs-Wolfe, ISW）效应及辅助数据的映射文件：MICE大挑战光锥模拟（MICE Grand Challenge Lightcone Simulation）。 **文件结构** `MICE_ISW_map_zmin_0.0_zmax_1.4_SBT_normal_nside_256.fits`：该文件为MICE模拟的主ISW映射文件，采用HEALPix（层次化等面积等纬度像素化）格式，nside=256，覆盖红移z=0至z=1.4的贡献，通过标准边界球贝塞尔变换（spherical Bessel transform, SBT）构建。 `MICE_alm_zmin_0.0_zmax_1.4_SBT_normal.txt`：上述映射对应的alm系数文件，可用于生成任意所需nside的映射。 `MICE_Full.zip`：包含MICE模拟在z=0至z=1.4红移范围内的ISW映射、alm系数及理论角功率谱（Cls）的压缩包。 `MICE_dz_02.zip`：与上述压缩包内容一致，但按dz=0.2的红移区间进行了划分。 **方法** 采用带有标准边界条件与导数边界条件的球贝塞尔变换、球谐缩放，以及Francis & Peacock（2010）近似方法。 **数据产品** - HEALPix（层次化等面积等纬度像素化）格式的ISW映射文件，nside=256，单位为开尔文（K）。 - 以ASCII格式存储的ISW alm系数文件，单位为开尔文（K），列依次为实部、虚部。 可通过以下Python代码生成任意所需nside的HEALPix映射： python import numpy as np import healpy as hp alm_fname = #provide name to alm file nside = #provide desired nside for map data = np.loadtxt(alm_fname, unpack=True) alm = data[0] + 1j*data[1] isw_map = hp.alm2map(alm, nside) 理论角功率谱（Cls，无量纲）的列信息如下： - `l`：球谐阶数l模态 - `cl_ii`：ISW自角功率谱 - `cl_id`：ISW-密度交叉角功率谱 - `cl_dd`：密度自角功率谱 - `cl_ii_limber`：采用林伯近似（Limber approximation）的ISW自角功率谱 - `cl_id_limber`：采用林伯近似的ISW-密度交叉角功率谱 - `cl_dd_limber`：采用林伯近似的密度自角功率谱 注：ISW映射与alm系数已预先乘以宇宙微波背景辐射温度Tcmb = 2.7255。 **引用说明** 请引用该Zenodo仓库的DOI进行学术引用。 **联系方式** 电子邮箱：[e-mail]