MAARBLE WP3 : Wave database ICD

Prepared by Yuri Khotyaintsev, IRF-Uppsala

Purpose

Perform a literature search and compile a list of the existing statistical wave databases in the radiation belts covering ULF and VLF bands. Define exactly which quantities should go into the database. The selection of quantities will be based on potential scientific impact, synergy with the other work packages and available resources. Define the layout of the summary plots.

General conventions

Formats

Cluster Exchange Format: http://caa.estec.esa.int/caa/documentation.xml

Standards

PSD definition (Propose & Brautigam)

FAC system definition for VLF/ULF (transformation matrix for ULF/VLF will be delivered as AUX datasets):

B is low-pass filtered below 1/600 Hz (ULF) and ¼ Hz /VLF).

z||B

y = z x R

x = y x z

For L* we have two options:

1) Use the Olson-Pfitzer Quiet model, which is what Sebastien and Didier are doing for the particle data

2) Use the Kp-dependent Tsyganenko-1989 model, which is more accurate but also more computationally labor intensive

Quality indicators can be used.

Table: Quality levels

Level

Description

0

Bad

1

Use with caution

2

Good

3

Very good: Manually verified

Parameters

When possible, all frequency bands should contain: power spectra of E and B, Poynting flux, polarization properties and propagation angles.

Table: Wave parameters

Name

Units

Description

Time

ISO time

Time tags

Frequency

Hz

Interval centred frequency tag

Frequency_BHW

Hz

Frequency bin half widths

BB_xxyyzz_fac

nT^2 Hz^-1

B Power spectral density

KSVD_fac

deg, deg

Direction of propagation (SVD) : polar and azimuthal angles.

ELLSVD

Unitless

Ellipticity of the polarization (SVD). Range: -1..1.

PLANSVD

Unitless

Planarity of polarization (SVD). Range: 0..1.

POLSVD

Unitless

Degree of polarization in the polarization plane (SVD).

Range: 0..1.

DOP

Unitless

3D degree of polarization defined in Samson (1973).

BMAG

nT

Magnitude of the DC magnetic field.

EE_xxyyzz_fac

mV^2 m^-2 Hz^-1

E Power spectral density

EESUM_xxyy_isr2

Sum of E Power spectral density in two measured components in the spacecraft spin plane

PV*,**

W/m^2/Hz, deg, deg

Poynting vector : amplitude, polar and azimuthan angles

*subject to availability of E measurement.

** for Pc3-5 we use zero parallel electric field approximation E.B=0. For higher frequencies we use dE.dB=0 (wave fields), which assumes presence of a single wave.

Space-based VLF database

Data Sources

Data will be used from Cluster and THEMIS projects.

The Cluster data is available from the Cluster active archive, http://caa.estec.esa.int. The Cluster data sets we want to use are summarized in the following table.

Table: Source data sets for Cluster

Name

Description

Comment

WHI_NATURAL

WHISPER measurement of Electric spectral power density under natural mode, 2-80 kHz

http://caa.estec.esa.int/caa_search/tmp_xml/C1_CP_WHI_NATURAL.CEF.XML

STA_PSD

STAFF-SA measurement of Power Spectral Density measurements of three components of the magnetic field and two components of the electric field in ISR2 reference frame, at 27 frequencies logarithmically distributed between 8 Hz and 4 kHz.

http://caa.estec.esa.int/caa_search/tmp_xml/C1_CP_STA_PSD.CEF.XML

STA_SM

STAFF-SA measurement of cross spectral matrices formed from 3 components of the magnetic field and 2 components of the electric field determined with either 1or 4s time resolution at 27 logarithmically distributed frequencies between 8 Hz and 4 kHz.

http://caa.estec.esa.int/caa_search/tmp_xml/C1_CP_STA_SM.CEF.XML

WBD_WAVEFORM_CDF

WBD measurement of high time resolution electric and magnetic waveform.

http://caa.estec.esa.int/caa_search/tmp_xml/C1_CE_WBD_WAVEFORM_CDF.CEF.XML

The THEMIS data...

Table: Source data sets for THEMIS

Name

Description

Comment

FFT

WB

Data products

We split all the science products into "general" and "specific" (for particular wave modes, etc).

General VLF data products

The general datasets will include all the data for 3 RE< R <10 RE and magnetic latitudes limited to 60 deg (to avoid the auroral zone).

Table: General VLF data products

Name

Time resolution

Data sources

Comment

CX_CP_AUX_MAARBLE_VLF*

Cluster STAFF-SA spectral matrices

CC_CP_AUX_MAARBLE_THX_WB_VLF**

THEMIS WB

*CX to be replace with the Cluster spacecraft number, e.g. C1.

**THX to be replace with the THEMIS spacecraft number, e.g. THA.

The CX_SA_VLF will be produced using the PRASSADCO code (SVD of spectral matrices[ Santolik et al, 2003]). The THX_WB_VLF will use a similar method based on SVD developed at IRF.

The parameters to be included in the general VFL data products are given in Table: Wave parameters.

Specific VLF data products

Specific data products will be based on manual selection of intervals containing clear chorus/Equatorial noise/etc signatures. These data sets will be used to study waves in detail, and verify the propagation characteristics of particular wave modes obtained from the “statistical” data sets.  

The only parameter included in this datasets will be time intervals.

Table: Specific VLF data products

Name

Data sources

Comment

CX_CP_AUX_MAARBLE_SA_VLF_BANDED

Cluster STAFF-SA spectral matrices

Banded emissions “manual” dataset

CX_CP_AUX_MAARBLE_VLF_CHORUS

Cluster STAFF-SA spectral matrices

Chorus “manual” dataset

CX_CP_AUX_MAARBLE_VLF_EQNOISE

Cluster STAFF-SA spectral matrices

Equatorial noise “manual” dataset

CC_CP_AUX_MAARBLE_THX_WB_VLF_BANDED

THEMIS WB

Banded emissions “manual” dataset

CC_CP_AUX_MAARBLE_THX_WB_VLF_CHORUS

THEMIS WB

Chorus “manual” dataset

CC_CP_AUX_MAARBLE_THX_WB_VLF_EQNOISE

THEMIS WB

Equatorial noise “manual” dataset

CX_CP_AUX_MAARBLE_WHI_VLF

Cluster WHISPER

UB chorus at small L, EC waves. Wait with this product.

AI to Ondrej: Add here some description of the way to select the data.

Space-based ULF database

Data Sources

Data will be used from Cluster, THEMIS, CHAMP, Swarm and GOES projects.

The Cluster data is available from the Cluster active archive, http://caa.estec.esa.int. The Cluster data sets we want to use are summarized in the following table.

Table: Source data sets for Cluster

Name

Description

Comment

EFW

3-dimensional Electric field vector in the inertial frame (i.e., vxB removed). The spin-axis component of the electric field is calculated with assumption of E.B=0 and with use of 2 electric field components measured in the spin plane and three magnetic field components. Typical sampling is 25 samples/sec.

http://caa.estec.esa.int/caa_search/tmp_xml/C1_CP_EFW_L2_E3D_INERT.CEF.XML

FGM

3-dimensional magnetic field vector sampled at 5 samples/sec.

http://caa.estec.esa.int/caa_search/tmp_xml/C1_CP_FGM_5VPS.CEF.XML

STA_SC

3-dimensional AC magnetic field vector for frequencies above 1 Hz. Typical sampling is 25 samples/sec.

Data is currently not available at the CAA. Data will be calibrated over large time intervals using LPP facilities (remote connection to calibration routines).

The THEMIS data...

Table: Source data sets for THEMIS

Name

Description

Comment

EFI

FGM

All CHAMP related data are archived at the Helmholtz GeoForschungsZentrum (GFZ) in

Potsdam, Germany and accessed through the Information Systems and Data Center

(ISDC), an online service portal providing access to data, documentation and software

tools. The website of ISDC is http://isdc.gfz-potsdam.de/index.php.

Table: Source data sets for CHAMP

Name

Description

Comment

FGM

3-dimensional magnetic field vector sampled at 1 sample/sec.

The Swarm data...

Table: Source data sets for Swarm

Name

Description

Comment

VFM

3-dimensional magnetic field vector sampled at 1 and 50 samples/sec.

The expected launch date of the Swarm mission is within the 2nd half of 2012.

EFI

3-dimensional electric field vector sampled at 2 samples/sec.

The expected launch date of the Swarm mission is within the 2nd half of 2012.

The GOES data...

Table: Source data sets for GOES

Name

Description

Comment

XXX

Frequency ranges

For the ULF waves we will use the typical Pc frequency ranges given in the table below.

Table: ULF frequency ranges

Name

Period

Frequency

Pc 1

0.2 - 5 s

0.2 - 5 Hz

Pc 2

5 - 10 s

0.1 - 0.2 Hz

Pc 3

10 - 45 s

22 - 100 mHz

Pc 4

45 - 150 s

7 - 22 mHz

Pc 5

150 - 600 s

2 - 7 mHz

Basic ULF Data products

This section contains basic data products, i.e. products not related to any specific wave mode.

General ULF data products

The general datasets will include all the data for 3 RE< R <10 RE and magnetic latitudes limited to 60 deg (to avoid the auroral zone), similar to VLF.

Table: General ULF data products

Name

Time resolution

Data sources

Comment

CX_CP_AUX_MAARBLE_ULF_PC1_SC*

10 s

Cluster EFW/STA_SC

Pc1 using STAFF-SC, 1-5 Hz frequency range, 0.5 Hz resolution (linear)

CX_CP_AUX_MAARBLE_ULF_PC12*

1 s

Cluster EFW/FGM

Pc1-2

CX_CP_AUX_MAARBLE_ULF_PC35*

60 s

Cluster EFW/FGM

Pc3-5

CC_CP_AUX_MAARBLE_THX_ULF_PC12**

1 s

THEMIS EFI/FGM

Pc1-2

CC_CP_AUX_MAARBLE_THX_ULF_PC35**

60 s

THEMIS EFI/FGM

Pc3-5

CC_CP_AUX_MAARBLE_CH_ULF_PC35

60 s  

CHAMP FGM

Pc3-5

CC_CP_AUX_MAARBLE_SW_ULF_PC35

60 s

Swarm

Pc3-5, Subject to successful launch and operations

CC_CP_AUX_MAARBLE_GO_ULF_PC35

60 s

GOES

Pc3-5

  *CX to be replace with the Cluster spacecraft number, e.g. C1.

  **THX to be replace with the THEMIS spacecraft number, e.g. THA.

The parameters to be included in the general VFL data products are given in Table: Wave parameters.

The lowest accessible frequency of the three STA_SC components is 0.35Hz. Neverthless due to strong spin effect in the low L value region, it is better to consider data above an higher frequency. Considering that FGM is available from DC to 2.5 Hz (for the 5Hz CAA product) and that the sensitivity curves of he two instruments intersect around 1Hz, STA_SC data set will start at 1Hz. For the Pc 1 range data sets of the two instruments will be merged.

Specific ULF data products

EMIC waves from Cluster and THEMIS selected by TBD algorithm.

Table: Specific ULF data products

Name

Comment

CX_CP_AUX_MAARBLE_ULF_EMIC

based on CX_ULF_PC12

CC_CP_AUX_MAARBLE_THX_ULF_EMIC

based on THX_ULF_PC12

Summary plots

Describe summary plot format, probably give some example. Can be nice to combine all our data products in some way.

Ground-based ULF database

Datasets: CARISMA, SAMNET, IMAGE

CARISMA ULF dataset

CARISMA ULF dataset contains power spectral density of the three magnetic field components: Bx (geographic North-South), By (geographic West-East), and Bz (vertical) from the selected CARISMA fluxgate magnetometer stations. The original data cadence is 1 Hz (starting 2005) and 0.2 Hz (prior to 2005). The station information is shown in the Table. For more details and original data download please visit www.carisma.ca.

Table: CARISMA station locations.

Station Code

Station Name

Geodetic Latitude

Geodetic Longitude

L-shell

RANK

Rankin Inlet

62.824

267.890

10.89

FCHU

Fort Churchill

58.763

265.920

7.44

GILL

Gillam

56.376

265.360

6.15

ISLL

Island Lake

53.856

265.340

5.15

PINA

Pinawa

50.199

263.960

4.06

Table: CARISMA data products.

Name

Resolution

Data Source

CC_CP_AUX_MAARBLE_STATIONCODE_ULF_PC35

60 s (since 2005)

300 s (before 2005)

CARISMA FGM