Welcome to IBEX Data Release 4 Maps, Ascii text data files, Papers and other information based on three years of operation.

IBEX Data Release 4

This fourth data release contains data used in the publication of McComas et al., 2012, "The First Three Years of IBEX Observations and Our Evolving Heliosphere" . IBEX results, together with in situ observations from the Voyager-1 and -2 spacecraft currently in the inner heliosheath, other supporting observations from several spacecraft, and a broad theory and modeling effort are producing a revolutionary new understanding of the outer heliosphere and its interactions with the local interstellar medium. In this release, we provide new ENA observations from IBEX, covering its first, second and third years of science operations. For questions about this or any other release, please email ibex_datareleases@lists.sr.unh.edu.

Individual data directories and related skymaps by type may be accessed by selecting the IBEX instrument of interest in the buttons above and then selecting one of the particular type of skymaps in the table (and referred to in the paper). Each page will allow you to explore all the skymap images or subsets by energy type or flux.

To download the data release as a tar file or to go to a table of plots and data selections per instrument, click on one of the links below. To learn more about the structure and content of the files contained in the various released directories, a detailed description follows.

Data Directory Structure and Naming Conventions

Within the data directories there are subdirectories associated with each type of skymap. The following keywords or phrases embedded into the subdirectory names indicate the processing options used to create the skymaps.

  • cg - Compton-Getting
  • tabular - Survival Probabilities
  • noSP - no Survival Probabilities
  • ram - Ram direction
  • antiram - Antiram direction
  • mapx - x identifies a particular set of orbits spanning 6 months.
  • yearx - x identifies a particular set of orbits spanning one year.

The 6-months and annual allsky maps are representative of the following IBEX orbits and dates:

Year Skymap # Start-End of Orbits or Arcs Dates
1 Map1 11-34 12/25/2008 – 06/26/2009
1 Map2 35-58 06/26/2009 – 12/26/2009
2 Map3 59-82 12/26/2009 – 06/26/2010
2 Map4 83-106 06/26/2010 – 12/26/2010
3 Map5 107-130a 12/26/2010 – 06/25/2011
3 Map6 130b-150a 06/25/2011 – 12/24/2011

Within each subdirectory there are a number of files associated with each sensor energy range that were used to create the skymap. File names that end with .txt (except -desc.txt) contain ASCII representations of particular data products. The data product with the file name "hv60.hide-trp-flux100-hi-2-ener.txt", for instance, identifies a flux (at 1 AU or at 100 AU if survival probabilities were applied) related file produced from the Hi instrument direct events (hide), triple (trp) coincidence types, energy sensor (2), with a type of 'energy' output data (ener), and that it is ASCII text data (.txt). The skymap plots with the .png suffix, accessible through the links in the "Plots" table below, are based on various calculations using these data products.

The -desc.txt files contain summary descriptions of the types and names of data files used to produce the plot files. Here is a listing of hv60.hide-trp-flux100-hi-2-desc.txt to illustrate:


Flux transported from 1 AU to 1.0 AU

Data Type Sample Filename
HS Flux hv60.hide-trp-flux100-hi-2-flux
HS Signal/Noise hv60.hide-trp-flux100-hi-2-fsnr
HS energies hv60.hide-trp-flux100-hi-2-ener
Samples per Pixel hv60.hide-trp-flux100-hi-2-numb
Total Exposure hv60.hide-trp-flux100-hi-2-fexp
Total Counts Data hv60.hide-trp-flux100-hi-2-cnts
Raw Orbit Data hv60.hide-trp-flux100-hi-2-fraw

Pixel Size: 6.000 x 6.000 degrees

Constructed from file(s):
o0011-hv60.hide-trp-flux1au-hi-2.txt
o0012-hv60.hide-trp-flux1au-hi-2.txt
o0013-hv60.hide-trp-flux1au-hi-2.txt
. . .
o0034-hv60.hide-trp-flux1au-hi-2.txt
With additional parameters:
         data spread 6 spin-ward 7 sun-ward degrees
         with range  7 spin-ward 7 sun-ward degrees 
         variance weighting disabled
         exposure weighting enabled
         nearest neighbor disabled
         Normal de-ram corrections
         Longitude-aligned orbit frames
         Sun-ward range decreases towards NEP
         Additional supporting files:
         o0011-hv60.hide-trp-fvar1au-hi-2.txt
         o0012-hv60.hide-trp-fvar1au-hi-2.txt
         o0013-hv60.hide-trp-fvar1au-hi-2.txt
. . . 
         o0034-hv60.hide-trp-fvar1au-hi-2.txt
         o0011-hv60.hide-trp-fexp1au-hi-2.txt
         o0012-hv60.hide-trp-fexp1au-hi-2.txt
         o0013-hv60.hide-trp-fexp1au-hi-2.txt
. . .
         o0034-hv60.hide-trp-fexp1au-hi-2.txt
         o0011-hv60.hide-trp-cnts1au-hi-2.txt
         o0012-hv60.hide-trp-cnts1au-hi-2.txt
         o0013-hv60.hide-trp-cnts1au-hi-2.txt
. . . 
         o0034-hv60.hide-trp-cnts1au-hi-2.txt
       
plot_title: 60d: hv60 hide trp
ener_title: ~0.71 keV

  

NOTE: Intermediate files, such as those listed as 'Constructed from" or "Additional supporting", are not provided as part of the Data Release.

Mono-Energetic Global Flux Maps

Some of the directories also contain a set of variable energy maps interpolated/extrapolated to a fixed energy.
The energy chosen is that of the center of the ESA channel in the s/c frame. These file
names are similar to the variable energy file names. E.g. hv60.hide-trp-mono_80-1.11-flux, is the hv60 cull, the hide data type (direct events from Hi), coincidence type
trp (triples), extrapolated to energy 1.11 keV (ESA channel 3).
There are fewer members to this family of products:

  • flux: the flux estimate
  • fvar: the variance (sigma squared) of the estimate
  • fsnr: the signal-to-noise (flux/sigma) of the estimate
  • desc: processing options
  • parm-0: which contains the average spectral slope.

File Headers

Each individual data product file features a header describing the processing options used to create it. Here is the header from one such file. int the data file, the comment header would be followed by an array of numbers formatted per line based on the numbers 30x60 (30 rows by 60 columns) in the first line, or 30 rows of declination by 60 columns of right ascension values. The data value units are provided in either the "desc=" or "title=" entries.

# 27:30x60:-5.0x-5.0:7x6:0:7
#
# Sat Sep 1 19:53:41 2012
#
# flux_translate
#
# -s matrix
#
# -0 dec (addresses incr. downwards)
# -1 ra (addresses incr. left->right)
#
# h_min=0.000000 h_max=559.000000 h_title='Total Counts'
# min_0=-90 max_0=90 num_0=30 title_0='Dec (deg)'
# min_1=0 max_1=360 num_1=60 title_1='R.A. (deg)'
# desc="'flux (ENAs / cm^2 s sr keV)'"
# skyframe=ECLIPJ2000 posframe=J2000
#
# chat=0 smearspread='0/0/0' calc='0/0/0'
# frame_epoch=914629271.873 resp_class=hi_triple zaxis_ra_deg=+274.476346 zaxis_dec_deg=-22.782473
# ram_ra_deg=+187.1048 ram_dec_deg=-3.4879 mtype_list='05,0A,0E' energy_list='12'
# rate_factor='1000' bg_rate=0.05870 bg_rvar=.0000012100 e_nominal='0.71'
# g_factor='0.000406114' inv_method='it3ptfive,20,0.5,f,h,1.5625' meth_opts='20,0.500000,f,h,1.562500'

Calculation Notes

Spectral figures in the paper were derived from maps at different energies.
Combined maps were calculated as:
(example of combining the first three maps)
;Weights (exposure times)
wt1=tau1/(tau1+tau2+tau3)
wt2=tau2/(tau1+tau2+tau3)
wt3=tau3/(tau1+tau2+tau3)
;Combined fluxes, Variances, signal-to-noise
flux=flux1*wt1 + flux2*wt2 + flux3*wt3
var=var1*(wt1)^2 + var2*(wt2)^2 + var3*(wt3)^2
snr=flux/( sqrt(var) )

IBEX Hi Observing Energetic Neutral Atoms In a higher range of energies

Plots and Data Directories

6-month Compton-Getting Corrected Maps

Compton-Getting maps adjust values after correcting for the speed of the spacecraft in relation to the direction of arrival of the ENAs.

The data directories:

hvset_cg_map1

hvset_cg_map2

hvset_cg_map3

hvset_cg_map4

hvset_cg_map5

hvset_cg_map6

6-month Maps

These maps represent the data before any corrections are made for speed of spacecraft or survival probability.

The data directories:

hvset_map1

hvset_map2

hvset_map3

hvset_map4

hvset_map5

hvset_map6

Yearly Maps, Ram Direction

These maps include data recorded from times when the aperture was pointed towards the hemisphere of the spacecraft’s motion. The maps do not include survival probability corrections.

The data directories:

hvset_noSP_ram_year1

hvset_noSP_ram_year2

hvset_noSP_ram_year3

Yearly Maps, AntiRam
Direction

These maps include data recorded at times when the aperture was pointed away from the hemisphere of the spacecraft’s motion. The maps do not include survival probability corrections.

The data directories:

hvset_noSP_antiram_year1

hvset_noSP_antiram_year2

hvset_noSP_antiram_year3

6-months, Compton-Getting and
Survival Probability Corrected Maps

Compton-Getting Tabular Maps adjust values after correcting for the speed of the spacecraft in relation to the direction of arrival of the ENAs and include adjustments taking into account ENA survival probabilty as they move from the outer heliosphere to 1 AU (location of IBEX).

The data directories:

hvset_cg_tabular_map1

hvset_cg_tabular_map2

hvset_cg_tabular_map3

hvset_cg_tabular_map4

hvset_cg_tabular_map5

hvset_cg_tabular_map6

Note: Survival probability correction procedures are documented in the paper in Appendix 2.

Survival Probability Lookup Maps

Survival Probability Maps account for the loss (extinction) of ENAs due to radiation pressure, photoionization and ionization via charge exchange with solar wind protons.

The data directories:

hvset_tabular_map1

hvset_tabular_map2

hvset_tabular_map3

hvset_tabular_map4

hvset_tabular_map5

hvset_tabular_map6

Note: Survival probability correction procedures are documented in the paper in Appendix 2.

Yearly Maps, Survival Probability Corrected, Ram Direction

These maps include survival probability corrected data recorded from times when the aperture was pointed towards the hemisphere of the spacecraft’s motion.

The data directories:

With Compton-Getting

hvset_tabular_ram_year1_cg

hvset_tabular_ram_year2_cg

hvset_tabular_ram_year3_cg

Without Compton-Getting

hvset_tabular_ram_year1

hvset_tabular_ram_year2

hvset_tabular_ram_year3

Note: Survival probability correction procedures are documented in the paper in Appendix 2.

Yearly Maps, Survival Probability Corrected, Antiram Direction

These maps include survival probability corrected data recorded from times when the aperture was pointed away from the hemisphere of the spacecraft’s motion.

The data directories:

With Compton-Getting

hvset_tabular_antiram_year1_cg

hvset_tabular_antiram_year2_cg

hvset_tabular_antiram_year3_cg

Without Compton-Getting

hvset_tabular_antiram_year1

hvset_tabular_antiram_year2

hvset_tabular_antiram_year3

Note: Survival probability correction procedures are documented in the paper in Appendix 2.

 

 

All Hi Data Directories and IDL Save Set

All IBEX Hi Data Directories IDL Save Set for Survival Probabilities

 

 

 

IBEX LoObserving Energetic Neutral Atoms In a LOWER range of energIES

Plots

Ram Maps

SC frame (orbits 11 through 150a),
without Survival probability, Signal-to-Noise mask threshold=3.

These maps include data recorded from times when the aperture was pointed towards the hemisphere of the spacecraft’s motion.

The Data Directory: map_ram

Antiram Maps

SC frame (orbits 11 through 150a),
without Survival probability, Signal-to-Noise mask threshold=3.

These maps include data recorded from times when the aperture was pointed away from the hemisphere of the spacecraft’s motion.

The Data Directory: map_wake

All Lo Data Directories and IDL Save Set

All IBEX Lo Data Directories IDL Save Set for Survival Probabilities

 

 

 

Survival Probability Tables

Survival Probabilities tables

Each data directory related to survival probability has information about a different aspect of the transport through the heliosphere:

  • deflection - angular deflection experienced between the termination shock and the observer
  • eloss - energy loss (or gain) between the termination shock and the observer
  • surv - survival probability that an ENA passing through the termination shock will make it to 1AU

For this release, the survival probabilities are only applied to the IBEX-HI data stream. Note that the energy loss is negligible, and the deflection angles in the inertial system are always smaller than 0.6 degrees or so.

Each directory has contains correction factors for data in the spacecraft frame (scf) and the inertial frame (1AU). The inertial frame (1AU) survival probabilities are used for the CG corrected data. The spacecraft frame factors are used for uncorrected data. The spacecraft frame files have the energy/direction shifts caused by the Earth/Spacecraft motion. This has a small effect on the survival probabilities (simply due to the energy shifts), but the deflection angles and energy shifts caused by this motion can be significant. The deflection and energy shift files are not applied by the IBEX pipeline software. In theory, these could be applied to the CG corrected data after the fact. However, it is important to note that the spacecraft frame correction factors for energy and angle contain elements of the CG correction and can yield confusing results when applied to the pipeline results.

The data layout per frame consists of the following. For the spacecraft frame, there is a column for each ESA step, and a row for each angle bin (1 degree bins). Each number gives the probability at that angle and ESA for survival. The probability per angle is interpolated to the center of any particular angular bin being evaluated.

In the inertial frame, the columns are the energies rather than ESA steps. These are applied to the IBEX images that are given on the variable energy grid. For each image pixel, we take the energy and angle and use a 2D interpolation to get the survival probability.

 

Release Detailed Description


IBEX orbits and dates used to construct 6-months and annual allsky maps:

Year Skymap # Start-End of Orbits or Arcs Dates
1 Map1 11-34 12/25/2008 – 06/26/2009
1 Map2 35-58 06/26/2009 – 12/26/2009
2 Map3 59-82 12/26/2009 – 06/26/2010
2 Map4 83-106 06/26/2010 – 12/26/2010
3 Map5 107-130a 12/26/2010 – 06/25/2011
3 Map6 130b-150a 06/25/2011 – 12/24/2011


############################################################################
This dataset includes the following IBEX products:
1. 6-month Maps in the SC frame
2. 6-month Maps in the HS Frame
3. 6-month Maps in the SC frame with Survival Probability
4. 6-month Maps in the HS Frame with Survival Probability
5. RAM Yearly Maps in the SC frame without Survival Probability
6. Anti-RAM Yearly Maps in the SC frame without Survival Probability
7. RAM Yearly Maps in the HS frame without Survival Probability
8. Anti-RAM Yearly Maps in the HS frame without Survival Probability
9. RAM Yearly Maps in the SC frame with Survival Probability
10. Anti-RAM Yearly Maps in the SC frame with Survival Probability
11. RAM Yearly Maps in the HS frame with Survival Probability
12. Anti-RAM Yearly Maps in the HS frame with Survival Probability
13. IBEX-Lo, Ram and Antiram, SC frame (orbits 11 through 150q),
without Survival probability, Signal-to-Noise mask threshold=3
14. Survival Probabilities for IBEX-Lo and IBEX-Hi (maps only).
############################################################################
Spectral figures in the paper were derived from maps at different energies.
Combined maps were calculated as:
(example of combining the first three maps)
;Weights (exposure times)
wt1=tau1/(tau1+tau2+tau3)
wt2=tau2/(tau1+tau2+tau3)
wt3=tau3/(tau1+tau2+tau3)
;Combined fluxes, Variances, signal-to-noise
flux=flux1*wt1 + flux2*wt2 + flux3*wt3
var=var1*(wt1)^2 + var2*(wt2)^2 + var3*(wt3)^2
snr=flux/( sqrt(var) )
############################################################################
Orbit culls and other data related to this release are locked on the isoc.
############################################################################

Best Sonified Skymap Plots and Data Combining Maps 1 to 6 Using Musical Encoding

The Auditory Information Design

The data that forms the basis for IBEX skymaps are 60 column by 30 rows arrays of numbers represented flux values. The columns represent longitude from 0 to 360 in 6 degree increments and the rows represent latitude from -90 to 90 in 6 degree increments. Each cell of data, therefore, represents a 6 degree by 6 degree section of sky.

In the visual maps, the data is presented using a Mollweide projection to provide a view of the entire sky as an egg-like shape. Each half arc of the sky from North to South, is represented in one column of data. The other half arc, completing a full great circle of the sky, is located in a different column and therefore different location in the visual map. The maps start on the left side at longitude 72 and moves to the right decreasing to 0 as in 72, 66, 60...12, 6, 0, then -6, -12, -18, -24, ... -174, -180/180, 174, ... to 72. The negative numbers are the equivalents of positive 180 to 360.

To sonify the data skymap, we liken the map to a musical staff (or stave) as shown here:File:Piano staff.png. The placement or location of the notes on the staff determine their pitch. Likewise, data cells in the skymap as assigned pitches out of a scale of a 7 note spanish gypsy scale comprised of 6 octaves (starting three octaves below 'C' and the scale features a flat 2nd, 6th and 7th). You can think of the map as overlaid with a musical staff as shown in the following image with the treble clef on top and bass clef below. skymap with musical staff overlaid

in the sonification, the data value in each cell controls the volume of the note at that vertical location on the staff. To illustrate this, if we reverse the blue gradient skymap image used above, we start to see the ribbon shape almost like musical notes on the staff, as in skymap with reversed skymap where the ribbon is darker, rather than lighter.. Now if we draw notes where the ribbon is showing, we get an image of a musical staff with a sequence of notes on it, just like a musical score: skymap with musical score overlaid with notes filled in.. If we play each column of data starting from the left side of the map to right, the notes heard in this case would start high, then descend through a sequence of ever lower notes, then start back up again. Because there are varying values in each cell, the sound is more akin to clusters of notes which come up and down in volume and so is not quite so simple as a single note melody, but this illustrates the basic concept.

In the sonification of IBEX skymaps, we present the rows of latitude data in two ways, as a chord of music per column, and as a relatively fast sequence of notes starting from the visually top latitude row (+90 degrees) down to the visually bottom latitude row (-90 degrees).

We use a nylon stringed guitar sound to convey the pitch information. Each guitar sound is relatively short (under 250 ms in general). We also use reverb to spread the sound out a bit and to give the brain a chance to hear decaying notes.

We value your input and experience using these sonifications, especially by those who are blind and/or visually impaired. Please send comments and feedback to sonification designer Marty Quinn, IBEX ISOC team, at martyq92@gmail.com.

Before we get present the IBEX skymaps as short musical type sounds, it's instructive to compare how relatively simple data sounds on a skymap. That way, when the data gets more complicated, it provides a basis for determining where change is present.

Learn to Listen to Skymaps as Music Through 9 Test Datasets

In the table below, we present structured test data that will help you train your ears to hear the structure and trends in the skymaps through the auditory display. These nine examples are organized into three regions where we have placed significantly high flux values, values you will hear as pitches played on a guitar. The regions include target latitudes of a high latitude, roughly equivalent to +45 degrees, a mid, center or 0 degrees latitude and a low latitude at -45 degrees. Each region is further differentiated by three trends including 1) an unchanging high flux data signal across all longitudes, 2) a high flux signal surrounded by a spread of 2 latitudes plus and minus with decreasing flux values in each direction and across all longitudes, and a changing flux signal in the target latitude as the longitudes change, with values starting low, increasing to near maximum, then decreasing again. You will hear a shaker sound as well. This represents the changing longitudes as described below in the header of the table. In the test data presentation, we only present each longitude's latitude values (there are 30 of them) as a chord of music. Since the data in all latitudes is of low value except for the target region, the notes in those latitudes cannot be heard even though they are being played.

location

of

learning values

 

One latitude of high values

Latitude strips per longitude as chord.

Latitude is pitch: +90 highest, -90 lowest.

Flux value is volume: higher flux values result in pitches that are louder.

Left to right on image maps to panning of sound in stereo L/R.

Actual longitude value is played at the top latitude (+90) of each column using the sound of a shaker. The shaker ranges in pitch based on longitude from lower pitched (and louder) to higher pitched (and softer) values.

 

A spread of five latitudes with high values

Latitude strips per longitude as chord.

Latitude is pitch: +90 highest, -90 lowest.

Flux value is volume: higher flux values result in pitches that are louder.

Left to right on image maps to panning of sound in stereo L/R.

Actual longitude value is played at the top latitude (+90) of each column using the sound of a shaker. The shaker ranges in pitch based on longitude from lower pitched (and louder) to higher pitched (and softer) values.

One latitude where data moves from low to high to low values

Latitude strips per longitude as chord.

Latitude is pitch: +90 highest, -90 lowest.

Flux value is volume: higher flux values result in pitches that are louder.

Left to right on image maps to panning of sound in stereo L/R.

Actual longitude value is played at the top latitude (+90) of each column using the sound of a shaker. The shaker ranges in pitch based on longitude from lower pitched (and louder) to higher pitched (and softer) values.

 

In the middle of the top half of the map

+45

 

in the center of the map

0 degrees

in the middle of the bottom half of map

-45

 

The Best Sonified Actual Data Skymaps

Energy

Sonified Skymaps - 'Score' Sonification - Quicker presentation for better perception of overall trends.

Latitude strips per longitude as chord.

Latitude is pitch: +90 highest, -90 lowest.

Flux value is volume: higher flux values result in pitches that are louder.

Left to right on image maps to panning of sound in stereo L/R.

Actual longitude value is played at the top latitude (+90) of each column using the sound of a skaker. The shaker ranges in pitch based on longitude from lower pitched (and louder) to higher pitched (and softer) values.

 

Sonified Skymaps -'Score' Sonification - Overall slower presentation for more latitude detail.

Latitude strips per longitude as fast note sequences from top to bottom or +90 to -90 latitude.

Latitude is pitch: +90 highest, -90 lowest.

Flux value is volume: higher flux values result in pitches that are louder.

Left to right on image maps to panning of sound in stereo L/R.

Actual longitude value is played at the top latitude (+90) of each column using the sound of a skaker. The shaker ranges in pitch based on longitude from lower pitched (and louder) to higher pitched (and softer) values.

Data .txt files (to access the data directory directly use this link: comb-map1to6)
0.71 keV
0.71 keV sonified map - lats per longitude strip as chord 0.71 keV sonified map - lats per longitude as quick melodies

Differential Flux (comb-map1to6-0.71-flux.txt)

Signal/Noise (comb-map1to6-0.71-fsnr.txt)

Variance (comb-map1to6-0.71-fvar.txt)

1.11 keV
1.11 keV sonified map - lats per longitude strip as chord 1.11 keV sonified map - lats per longitude as quick melodies

Differential Flux (comb-map1to6-1.11-flux.txt)

Signal/Noise (comb-map1to6-1.11-fsnr.txt)

Variance (comb-map1to6-1.11-fvar.txt)

1.74 keV
1.74 keV sonified map - lats per longitude strip as chord 1.74 keV sonified map - lats per longitude as quick melodies

Differential Flux (comb-map1to6-1.74-flux.txt)

Signal/Noise (comb-map1to6-1.74-fsnr.txt)

Variance (comb-map1to6-1.74-fvar.txt)

2.73 keV
2.73 keV sonified map - lats per longitude strip as chord 2.73 keV sonified map - lats per longitude as quick melodies

Differential Flux (comb-map1to6-2.73-flux.txt)

Signal/Noise (comb-map1to6-2.73-fsnr.txt)

Variance (comb-map1to6-2.73-fvar.txt)
4.29 keV
4.29 keV sonified map - lats per longitude strip as chord 4.29 keV sonified map - lats per longitude as quick melodies Differential Flux (comb-map1to6-4.29-flux.txt

Signal Noise (comb-map1to6-4.29-fsnr.txt)

Variance (comb-map1to6-4.29-fvar.txt)

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