CO5BOLD hydrodynamic Quiet Sun model

This is an early model atmosphere extending into the chromosphere calculated with CO5BOLD in 2001-2003 and published in Wedemeyer et al. (2004). The model has no magnetic field included and uses grey (i.e., frequency-independent) radiative transfer and can thus be understood as simplified (very) quiet Sun model. Time series of synthetic mm continuum intensity maps have been published by Wedemeyer-B. et al. (2007) (therein referred to as model A, W04).

Model properties

  • Target: (very) quiet Sun (no magnetic fields)

  • Time series with 60 snapshots, cadence = 10s

  • Dimensions (x,y,z): 5.6 Mm x 5.6 mm x 3.1 Mm

  • Grid points: 140 x 140 x 200

  • Height range (z):  -1377.30 km (bottom, convection zone) to +1705.30 km (top, chromosphere)

  • Grid resolution: horizontal: 40 km, vertical: 46 km at the bottom in the convection zone decreasing to 12 km for all layers above z = −270 km.

  • Magnetic field: none

Available model data

A total of 60 time steps with a cadence of 10s are currently provided. 

All data can be downloaded from the directory There is a g'zipped tar file for each time step, which contains 7 FITS files each. Each of these FITS files contains a data cube of dimensions 140x140x200 for one of the physical quantities in the table below. The FITS files are named like this: co5bold_w04hdgr_seq1_itXXX_YY.fits   where XXX is the number of the time step (e.g., 000) and YY the physical quantity (e.g., tg, see the column "symbol" in the table below). For instance, co5bold_w04hdgr_seq1_it008_vz.fits contains the vertical velocity component in time step it=008 and is included in the file co5bold_w04hdgr_seq1_it008.tar.gz. Each tar.gz file has a size of 93MB and the whole sequence thus 5.5 GB. The height axis is provided in a separate FITS file.

The whole sequence can be downloaded as a single tar.gz file: (Please note that this file has a size of 5.5 GB!)

Quantity Symbol Unit
Gas density rh g/cm3
Interal energy ei erg/g
Gas temperature tg K
Gas pressure pg dyn/cm2
Velocity, x-component vx cm/s
Velocity, y-component vy cm/s
Velocity, z-component vz cm/s
Height axis (file: co5bold_w04hdgr_seq1_z.fits) z km
Time (file: co5bold_w04hdgr_seq1_time.fits) time s

How to load the data in IDL: After downloading, simply use the READFITS function, e.g.:


If the file is found, the variable "data" will contain an array (here 3D) for the corresponding physical quantity.

Axes (cell centers) in units of km:

x=findgen(140) * 40.0 + 20.0

y=findgen(140) * 40.0 + 20.0

The height axis in units of km (cell centers) is contained in this file: co5bold_w04hdgr_seq1_z.fits

The exact times of the snapshots in seconds are contained in this file: co5bold_w04hdgr_seq1_time.fits

Synthetic observables

  • Continuum intensity images for 0.3mm, 1.0mm, 3.0mm and 9.0mm and different view angles from mu=1.0 (disk-centre) to mu=0.2 (close to the solar limb); sequence of 60 snapshots with 10s cadence. See here.

Simulated ALMA observations

  • To be added.


Published Jan. 12, 2016 10:47 PM - Last modified Feb. 15, 2019 2:04 PM