May 30, 2024:  PhoSim v6.0.1 is available


Forgot new cfitsio file and Tess instrument files


May 24, 2024:  PhoSim v6.1 is available!


The 24th major release of the Photon Simulator (PhoSim) is completed, tagged, and validated as PhoSim v6.1!  Some highlights:


1)  PhoSim v6.1 has several new improvements.


    -The largest improvement is the complete ab initio physical implementation of coating interactions on all optical surfaces including a/r coatings, protective coatings, etc. and some augmentation of multilayer physics.  All coatings also allow for inhomogenous thickness, and the light responds accordingly.

    - We also updated various measuring tools, added more example catalogs, flexibility in the SED normalizing point, adjusted airglow levels, spectra, and variability based on careful photometric studies, implemented correlated time-dependence of aerosol distributions, added absorption in materials, and streamlined the installation scripts and dependencies to work on more systems.

    -The wide-field survey telescope (WFST) was implemented (W. Luo).

    -Various improvements were made to the Pan-STARRS implementation (G. Magnier).

    -The WIYN telescope coatings and contamination levels were implemented.

    -The Rubin optics coatings and contamination levels were completely redone replacing old methods.

    -There are a number of bug fixes and many new optimizations that improve performance as well.


2)  All documentation (tutorials, documentation, links to reference material, etc.) and instructions to get the code are at:   https://www.phosim.org


3)  The fifth reference paper was completed.  Follow the technical links for more information.


4)  We are also creating more tools/APIs related to machine learning/AI.


5)  We're attempting to facilitate the implementation of many more telescopes much more rapidly, which some of the improvements simplify.    To do this, we are building a number of tools as well as simplifying the interfaces for implementation of telescopes.  Please contact us if you want to collaborate on any telescope.


Feb 14, 2024:  PhoSim v6.0.13 is available


Updated configure script to be bash compliant and updated cfitsio/fftw (EM)


Feb 7, 2024:  PhoSim v6.0.11 is available


Fixed Pan-Starrs optics files which led to out of focus images


Feb 2, 2024:  PhoSim v6.0.10 is available


Changed scripts to bash since some distributions of linux do not include csh


Dec 13, 2023:  PhoSim v6.0.9 is available


Expanded and made more accurate microroughness array


Dec 12, 2023:  PhoSim v6.0.8 is available


Fixed bug in new coordinate system for user specified perturbations


Oct 23, 2023:  PhoSim v6.0.6 is available


Fixes pupil screen resampling which caused JWST error


Sep 8, 2023:  PhoSim v6.0.5 is available


Fixes rare bug for transmission of uncoated surfaces transmission


Aug 23, 2023:  PhoSim v6.0.4 is available


Fixes the optimization for monochromatic SEDs 


Jul 19, 2023:  PhoSim v6.0.2 is available


Fixes array size for much larger screens.


Jul 12, 2023:  PhoSim v6.0.1 is available


Fixes an error in scattering normalization


Jul 11, 2023:  PhoSim v6.0 is available!


The 23rd major release of the Photon Simulator (PhoSim) is completed, tagged, and validated as PhoSim Six (PhoSim v6.0)!  A few announcements:

1)  PhoSim Six has significant improvements in performance.  You should notice typically 33% improvements in speed, depending on your computing architecture and telescope & settings.  There are a number of changes that made this possible, and the improvements should allow us to continue to improve on performance in upcoming releases.  PhoSim Six also implements both a complete physical simulation of microroughness and  a self-consistent physical interaction of contamination (see below).    There are a number of bug fixes as well.

2)  The documentation has been migrated to a single site that has the address:


https://www.phosim.org


This should allow us much more flexibility and it should be much easier to find what you need.  The downloads, issue tracking and the repository itself will still be at the bitbucket site, but all of the documentation will move to phosim.org.  Please link to this new site, so we can continue to grow PhoSim.

3)   We are building a page with links to other codes the either:  1) produce phosim inputs,  2) produce phosim outputs or 3) embed phosim in an analysis loop.   If you have a code that does any of these, please reach out and we can add your link and work to modify aspects of the APIs to make it work easier for you as well.

Contaminated Unpolished Mirror with PhoSim
Clean Polished Mirror with PhoSim

Oct 6, 2022: PhoSim v5.7 is available!

The 22nd major release of the Photon Simulator (PhoSim) is completed, tagged, and validated as PhoSim v5.7! 

Important new improvements in v5.7 include: various updates to the instrument designs including Rubin/LSST, JWST, WIYN; various computational efficiency improvements including buffers and bright star optimizations; a number of updates to CMOS simulations with applications for JWST including better read modes, cosmic ray rejection, and saturation handling; allowing photon non-interaction regions on sensors; and a number of improvements for simulation of gratings including an optimization that pre-calculates trajectories once to allow as fast simulation as non-grating interactions. The K-DRIFT (KASI-Deep Rolling Imaging Fast-optics Telescope (a linear-astigmatism-free three-mirror optical system (LAF-TMS) for low surface brightness imaging survey) telescope has also been fully implemented.

There is also a new tutorial (tutorial 22) and a corresponding script that allows you to seamlessly take an image from a real telescope and generate an input catalog with the image at the correct location, angular scale, rotation, and intensity to use with PhoSim. (Note: you can of course continue to manually modify these properties to use an input image in any creative way (see tutorial 16) and of course use synthetic objects by hand or through auto-generated catalogs).

You can download the new version at the tagged release page and follow the documentation through the main site. Release notes are available at the v5.7 release notes page.


JWST LMC Simulation with PhoSim

Apr 13, 2022: PhoSim v5.6.11 is available

Fix for partial groups for CMOS reads that resulted in seg faults

Apr 13, 2022: PhoSim v5.6.10 is available

Extended dome light SED more into IR

Mar 31, 2022: PhoSim v5.6.9 is available

Handled saturated pixels on first CMOS read

Mar 31, 2022: PhoSim v5.6.8 is available

Improvements to CR filtering for CMOS reads, and file transfer issue fix for some read sequences

Mar 30, 2022: PhoSim v5.6.7 is available

Improvements to CMOS-style reads to allow for up-the-ramp-style readouts and more flexibility in read sequences

Mar 28, 2022: PhoSim v5.6.6 is available

More adjustments to bright star optimization for space-based telescopes

Mar 17, 2022: PhoSim v5.6.5 is available

Made JWST sensors have CMOS-style blooming

Mar 11, 2022: PhoSim v5.6.4 is available

Adjustments to various buffers for bright star optimizations, wavelength region for NirCam, coarser dynamic optimization, error in coating calculation for mirrors with no coating, error in dynamic optimization early in initialization

Mar 8, 2022: PhoSim v5.6.3 is available

Slight adjustments for JWST optics deformations.

Mar 4, 2022: PhoSim v5.6.2 is available

Fixed rare segmentation fault with particles and suppressed warning for space-based telescopes.

Feb 8, 2022: PhoSim v5.6 (and v5.6.1) is available!

The 21st major release of the Photon Simulator (PhoSim) is completed, tagged, and validated as PhoSim v5.6!

Important new improvements in v5.6 include: the addition of a number of generic telescopes for quick aperture size comparisons, a number of new small and large telescopes as well as updates for previously implemented telescopes (esp. JWST), automatic transmission calculations for uncoated surfaces, the ability to read out sensors for drift scanning and corresponding ability to turn of rotation tracking, the ability to automatically use the WCS from truth images, tools for morphology testing, and a full global representation of artificial light. There are also three new tutorials. We have updated information about the implemented observatories and background simulation options as well. Another important aspect of the PhoSim v5.6 release is a substantial number of changes that increase the overall speed and performance by streamlining the overall set of computations, reducing the memory footprint, and improving thread management. For most configurations, you will see a 30% to 50% improvement over v5.5 (and much more compared to earlier versions).

You can download the new version at the tagged release page and follow the documentation through the main site. Release notes are available at the v5.6 release notes page.


Sky Rotation in PhoSim

Jan 25, 2022: PhoSim v5.5.5 is available

Fixes bug in CMOS calculation when more than one snap is used

Aug 5, 2021: PhoSim v5.5.4 is available

Fixes rare bug when altitude is unspecified with some compilers

Jul 29, 2021: PhoSim v5.5.3 is available

Fixes multi-threading when atmosphere diffraction is turned on

Jul 9, 2021: PhoSim v5.5.1 is available!

The 20th major release of the Photon Simulator (PhoSim) is completed, tagged, and validated and is called PhoSim v5.5.1

Some highlights from PhoSim v5.5.1 include: completion of the self-consistent absorption/scattering/dispersion physics for normal and background light with implementations of atmosphere constituents, an improvement to cloud statistics and overall representations, expansion to atmosphere spatial variations, improvements to sensors, a major update to the Rubin (LSST) focal plane and more options for sensor geometry, general speed and performance improvements, and a variety of new diagnostic output options. There have been updates to documentation as well.

April 21, 2021: PhoSim v5.4.11 is available.

Fixed bug in optimization of transmission for space-based telescopes

March 18, 2021: PhoSim v5.4.10 is available.

More retries for CONDOR

March 15, 2021: PhoSim v5.4.9 is available.

Some material files missing for CONDOR implementation

March 11, 2021: PhoSim v5.4.8 is available.

Incorrect file transferred caused some non-convergence of perturbations

March 10, 2021: PhoSim v5.4.7 is available.

Possible memory problem on some compilers

March 2, 2021: PhoSim v5.4.5 is available.

Updated atmosphere parameter passing to make more robust for different compilers

Feb 19, 2021: PhoSim v5.4.4 is available.

Restructured atmosphere class which may solve issues on some compilers

Feb 16, 2021: PhoSim v5.4.3 is available.

Added --nothreadatm to not multithread atmosphere calculation which is causing memory problems on some systems; more files transferred in CONDOR

Feb 8, 2021: PhoSim v5.4.1 is available.

Removed extraneous reference from CONDOR

Feb 2, 2021: PhoSim v5.4 is available!

The 19th major release of the Photon Simulator (PhoSim) is completed, tagged, and validated and is called PhoSim v5.4.

Some highlights from PhoSim v5.4 include: detailed photon-cloud interactions, detailed physics improvements on turbulence representations, additional polynomial surface perturbation capabilities, simplication and generalization of instrument & site characteristics (ISC), capabilities for individual coating & electrical properties for individual sensors, reduction in the number of required ISC files,expansion of blooming/midline capabilities, various improvements in optimizations for different telescopes, and general increase in the speed of simulations. There have been more tutorials added and more updates to documentation as well.

January 11, 2021: PhoSim iPoster

A PhoSim iPoster is available at the January AAS Meeting

December 17, 2020: PhoSim v5.3.23 is available

Fix of rare cosmic ray bug

December 14, 2020: PhoSim v5.3.22 is available

Error in CONDOR implementation

December 11, 2020: PhoSim v5.3.21 is available

Changed directory reference for CONDOR implementation

December 10, 2020: PhoSim v5.3.20 is available

Changed directory reference for CONDOR implementation

December 9, 2020: PhoSim v5.3.19 is available

More CONDOR fixes

December 3, 2020: PhoSim v5.3.15 is available

More CONDOR fixes

December 2, 2020: PhoSim v5.3.14 is available

More CONDOR fixes

December 2, 2020: PhoSim v5.3.13 is available

More CONDOR fixes

November 30, 2020: PhoSim v5.3.12 is available

Fixed CONDOR for variable cloud height screens

October 28, 2020: PhoSim v5.3.11 is available

Fixed module B for JWST instruments

October 2, 2020: PhoSim v5.3.10 is available

Fixed HSC file and fixed telescopemode 0 for complex optical systems

September 30, 2020: PhoSim v5.3.8 is available

Fixed HSC plate scale and segmentation

September 24, 2020: PhoSim v5.3.7 is available

Mistake in HSC focal plane

September 17, 2020: PhoSim v5.3.6 is available

Flipped subaru HSC focal plane

September 16, 2020: PhoSim v5.3.5 is available

Makes further adjustments to polynomial perturbation representations

September 10, 2020: PhoSim v5.3.4 is available

Further adjustments to Subaru HSC focal plane

September 10, 2020: PhoSim v5.3.3 is available

Makes adjustments to Subaru HSC focal plane, ADC configuration, and sensors

August 31, 2020: PhoSim v5.3.2 is available

Added missing file for Subaru HSC

August 13, 2020: PhoSim v5.3.1 is available

Fixes crashing bug with some linux distributions

July 16, 2020: PhoSim v5.3 is available!

The 18th major release of the Photon Simulator (PhoSim) is completed, tagged, and validated and is called PhoSim v5.3.

Some highlights from PhoSim v5.3:

You can download the new version at the tagged release page and follow the documentation through the main site. As always, please file tickets for bugs at the issue tracker page and feel free to email for anything else.

July 6, 2020: PhoSim v5.2.13 is available

JWST filter numbers incorrectly labelled.

July 2, 2020: PhoSim v5.2.12 is available

JWST diameters wrong for some filters.

July 2, 2020: PhoSim v5.2.11 is available

JWST perturbation data not correct for long wavelength channel

June 25, 2020: PhoSim v5.2.10 is available

Better thermal expansion for JWST mirrors.

June 23, 2020: PhoSim v5.2.9 is available

Fix for space-based instruments not having diffraction working properly because of v5.2.7 changes.

June 4, 2020: PhoSim v5.2.8 is available

Incorrect tracking for space-based instruments.

May 1, 2020: PhoSim v5.2.7 is available

Unnecessary calculation for space-based instruments that was crashing on some linux distributions.

April 29, 2020: PhoSim v5.2.6 is available

Fixes for JWST opto-mechanical capabilities.

April 28, 2020: PhoSim v5.2.5 is available

Debugging some failures on JWST opto-mechanical capabilities.

April 28, 2020: PhoSim v5.2.4 is available

More fine tuning of JWST opto-mechanical capabilities.

April 23, 2020: PhoSim v5.2.3 is available

More fine tuning of JWST opto-mechanical capabilities.

April 22, 2020: PhoSim v5.2.2 is available

Fixes the JWST data files for the opto-mechanical capabilities.

March 27, 2020: Large PhoSim LSST Survey available

A substantial survey simulation for the LSST Rubin Observatory with a series of exposures of differing observing conditions and configurations using PhoSim v5.1. It is being generated by A. Mahmood and M. Saleem and is available at the Bellarmine site using Open Science Grid resources. The data continues to accumulate.

January 5, 2020: PhoSim v5.2.1 is available

This version converges better in calculating optics deformations in some rare cases.

December 12, 2019: PhoSim v5.2 is available!

The seventeenth major release of the Photon Simulator (PhoSim) is completed, tagged, and validated. We are continuing to push towards a complete ab initio Monte Carlo simulation code of the physics of astronomical observations.

Major improvements in v5.2 are: 1) a complete ab initio physics simulation of cosmic rays and terrestrial particles, 2) an improved self-consistent atmosphere scattered moonlight/sunlight & absorption calculation, 3) a variety of simplified interface changes as well as new astronomical emission & reflection models, 4) continued refinement and updates to opto-mechanical simulation capabilities including and 5) the implementation of physical large angle scattering from surfaces.

Other v5.2 improvements include: additional options and updates to velocity saturation, capability of generated catalogs having offset center from telescope pointing useful for a data challenge mosaic, better background buffers for small chips, additional quadratic term for aspheres for some optical designs, updated sensor interactions positions in event files, mirrors allowed to rotate with respect to camera for perturbations, simpler generic telescope options, fixed visualizer for curved focal planes, RGB curves for eye model, update of colors to yale bright star catalog, big dipper example catalog, update to condor options, various optimization speed up for background generation, update to collisional airglow intensity, update to WIYN mirror deformation, Cousins filters for generic telescope, additional physics parameters in GUI, and implementation of remote sensing capabilities. In addition, as usual a variety of bug fixes and software standards/reorganization was also done.

You can download the new version at the tagged release page and follow the documentation through the main site. As always, please file tickets for bugs at the issue tracker page and feel free to email for anything else.

October 3, 2019: PhoSim v5.1.7 is available

More CONDOR HPC system fixes.

September 28, 2019: PhoSim v5.1.6 is available

More CONDOR HPC system fixes.

September 26, 2019: PhoSim v5.1.5 is available

This patch fixes a number of issues related to running PhoSim with CONDOR HPC systems.

August 30, 2019: PhoSim v5.1.4 is available

This patch makes a simpler default generic telescope and improves the examples.

July 16, 2019: PhoSim v5.1.3 is available

This makes background simulation of smaller chips more efficient.

July 12, 2019: PhoSim v5.1.1 is available

This fixes the scaling of background buffers for faster background simulations.

June 14, 2019: PhoSim v5.1 is available!

The sixteenth major release of the Photon Simulator (PhoSim) is completed, tagged, and validated. We are continuing to push towards a complete ab initio Monte Carlo simulation code of the physics of astronomical observations.

One of the major improvements in this version is the new capability of using PhoSim's internal catalog generator to generate data challenges automatically. This is accomplished by the fact that the generated stars & galaxies are now repeatable. So different images taken at different times and different configurations (filter, airmass, etc.) will receive the same galaxies & stars with the same properties. So a series of images can be generated and combined in the same manner as in an observing campaign. This can all be done with only six commands as shown at the end of the PhoSim tutorial.

Furthermore, the PhoSim internal catalog generator now has a variety of details to generate realistic images-- the stars have reasonable densities as a function of latitude and a variety of realistic SEDs, and the galaxies have reasonable densities, sizes & redshifts, complex morphologies (spirals, irregular), and realistic SEDs including color gradients. User-supplied catalogs can, of course, still be used for other representations of the Universe, and objects can be added to the internally generated catalogs.

Another major set of changes is the significant improvement of overall background simulation speed, which is often the slowest part of the simulation. We have simplified the background optimization options, so now there are simply 3 options to generate background: single photon, the standard approximation, and the quick background option.

Other improvements in v5.1 include: fixes of various possible memory leaks, work to unify atmosphere parameterization, implementation of the LSST collimated beam projector, various ghost optimization fixes, generalization of rayleigh scattering, interpixel capacitance, postpixel correlations, additional background validation, expansion to more asphere terms, update to HSC design, additional angle in 3-D galaxy models for edge on galaxies, fixes to deCam filters, fixes to background validation, better bright star optimization for space based telescopes, row/column lithography errors, various fixes to edge physics for glowing edge and expansion to include active region, and change of the default telescope to "generic".

You can download the new version at the tagged release page and follow the documentation through the main site. As always, please file tickets for bugs at the issue tracker page and feel free to email for anything else.

May 1, 2019: PhoSim v5.0.5 is available

Fixes condor file submission issue.

April 12, 2019: PhoSim v5.0.4 is available

Fixes approximate WCS on rotated and offset chips.

March 27, 2019: PhoSim v5.0.3 is available

Fixes for a segmentation fault on certain systems.

March 25, 2019: A new library of PhoSim-compatible Spectral Energy Distributions (SEDs) is available.

The new Library of SEDs is available. We have adapted the extensive library at the Spanish Virtual Observatory and STScI into PhoSim formats and organized into a single tar file.

December 14, 2018: PhoSim v5.0.2 is available

Compiler flag issue has been fixed.

December 12, 2018: PhoSim v5.0 is available!

The fifteenth major release of the Photon Simulator (PhoSim) is completed, tagged, and validated. This contains a major fundamental upgrade (hence, v5.0) that we describe below as well as 150+ other changes.

We are continuing to push towards a complete pure ab initio Monte Carlo simulation code. To that end, this release contains a major upgrade where we have now fully represented the complete physics of the deformation of optics! Thus, PhoSim does a complete opto-mechanical simulation of any telescope. It uses the deformation of the three-dimensional mirror and lens shapes due to thermal changes and elastic, actuator, and gravitational forces to predict the exact surfaces of the optics prior to complete optical raytracing. The approach uses a number of novel numerical techniques and couples a number of physics modules. The environment is simulated as well as the response of the control system for active optics telescopes. It is implemented in a very efficient manner, and the calculation is fully multithreaded so you will barely notice a run-time speed change for chip-scale simulations. The complete detailed description is described in Peterson et al. 2019, ApJ 873, 98. Here is an example of the mirror control simulation.

Other physics improvements in v5.0 include: complete dome seeing physics, Milky Way structure of generated star catalog, repeatability in generic catalog production, improvements to weather modelling, sky brightness validation, and wind shake implementation. The usability improvements include the splitting of bright star between multiple cores, Hubble tuning fork/jupiter & moons examples, better multithreading efficiency, HA & Sidereal time in header, additional tabs in the GUI, more operation parameter in the GUI, more numerical parameters in the GUI, editing of instrument and site files in the GUI, implementation of Galileo's telescope, and updates to various telescopes/cameras. The full list is available on release notes page.

You can download the new version at the tagged release page and follow the documentation through the main site.

As always, please file tickets for bugs at the issue tracker page and feel free to email for anything else.

October 3, 2018: PhoSim v4.0.4 is available

This patch fixes a bug in the sensor data of certain telescopes. In particular, the bug removed all photons from Subaru simulations.

August 22, 2018: PhoSim v4.0.3 is available

This patch fixes a bug in the segmentation of LSST wavefront sensors, and adds the hour angle and local sidereal time to the image header.

August 17, 2018: PhoSim v4.0.2 is available

This patch fixes a bug in dispersion at low altitudes, re-centers the OPD calculation for off-axis pointings, and unnecessary print statements when dust is on.

August 16, 2018: PhoSim v4.0.1 and v3.7.16 is available

These patches improve performance for large multithreaded environments.

June 8, 2018: PhoSim v4.0 is available!

The fourteenth major release of the Photon Simulator (PhoSim) is completed, tagged, and validated. Its called PhoSim v4.0. As the version number implies, it is probably the most significant upgrade for a number of reasons. There have been 400+ improvements and a number of major changes.

First, there is now a PhoSim GUI (Graphical User Interface)! This should be particularly helpful to busy new users as it is in general much more intuitive than reading pages of documentation. After compiling phosim, it is run simply with the command "phosim_gui". See the tutorials.

Second, the required inputs has now been simplified to be nothing! Previously, a large number of parameters were required to describe pointing, sun/moon position, time, etc., but now these are entirely optional. You now can simply set any parameter that is important, and let PhoSim self-consistently calculate the rest or choose them from appropriate distributions. This applies to all parameters. So with no inputs, PhoSim will simply make a realistic typical observation. If you want to point at a particular ra/dec, just use those commands. If you want the Moon below the horizon, then add that in, but you will no longer have to figure out how to calculate what you consider to be nuisance parameters for your study.

Third, there are a few simple catalog options to make quick catalogs: a star grid option, a random star maker with correct brightnesses, a random galaxy maker with correct brightnesses/sizes/shapes, and an example using the Yale Bright Star Catalog. There is also integration with ds9 (by using --ds9) when PhoSim completes and integration with the PhoSim visualizer (by using --visualizer) when event files are made to look at the ray trajectories.

Finally, there have been a large number of technical improvements. Some of the important ones include: a series of complex galaxy morphology models and nebulae models, an ab initio atmospheric dispersion calculation, greater self-consistency of 3-d background & opacity calculations, fixes for wavelength & spatial dependence for background, time correlation of clouds, improvements for CMOS readout systems & alternative chip materials, options to calculate precession/nutation/aberration, and various updates to JWST NIRCAM, WIYN ODI, Subaru HSC, and LSST data. The full list is available on release notes page.

You can download the new version at the tagged release page and follow the documentation through the main site.

As always, please file tickets for bugs at the issue tracker page. We are currently expanding the GUI, so email me suggestions based on your experience.