Transcript Diapositiva 1

BC/MPO/SERENA
Scientific Objectives
Anna Milillo
and the SERENA team
Hermean environment
(from Milillo et al., SSR, 2005)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Instrument package on board BepiColombo/MPO
SERENA
NPA-IS
Search for Exospheric Refilling
and Emitted Natural Abundances
Neutral Particle Analysers - Ion Spectrometers
Units:
ELENA: Emitted Low-Energy
Neutral Atoms
STROFIO: Start from a ROtating
FIeld spectrOmeter
MIPA: Miniature Ion
Precipitation Analyser
PICAM: Planetary Ion CAMera
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Main scientific objectives
of each unit
NPA:

ELENA investigates the Hermean escaping neutral gas
(strongly linked to its surface), and the processes
responsible of such a population.

IS:
STROFIO investigates the exospheric gas composition.

MIPA investigates the plasma precipitation toward the

PICAM
surface of Mercury.
investigates the exo-ionosphere extension and
composition.
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
SERENA vs Hermean environment
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Targets
Exosphere composition and spatial
distribution and dynamics
Search for exo-ionosphere and its
relation with neutral atmosphere
Surface release processes
Atmosphere/magnetosphere exchange
and transport processes
Escape, source/sink balance,
geochemical cycles
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
SERENA scientific objectives
1. Chemical and elemental composition of the
exosphere
2. Exo-ionosphere composition and distribution
3. Surface emission rate and release processes
4. Plasma precipitation rate
5. Particle loss rate from Mercury’s environment
6. Gas density anisotropies
•
Remote sensing of the surface composition
• Magnetosphere structure and dynamics
• Planetary response to SW variations
• ENA imaging (comparative solar-planetary
relationship)
• Heavy ion sputtering products
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj:1
Exosphere composition
The estimate of the exospheric densities is
derived from observations and models.
The scale height for each species is derived
by assuming a temperature T=500 K for
volatiles and T=5000 K for refractory
(Leblanc et al., 2004)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj:1
Neutral
Species
H
He
Li
C
N
O
Ne
Na
Mg
Al
Si
S
Cl
Ar
K
Ca
Fe
Ni
Kr
Xe
H2
OH
Expected range of the ion/neutral densities in
Mercury's close-to-planet environment
Neutral density Range
Photo(observed)
ionization
at 400 km
lifetime
–3
cm
s
9
–2
1160 (1330)
310
410 -200 (20)
5.1106
500 (330)
31011
5 - 2104 (2600)
1.7106
190
< 8.4107
810–4 - 4
4.1102
96
11011
310–1 - 1600
2.6104
83
51010
110–1 - 500
5105
72 (83)
< 31011
310–1 – 1600 (160)
5105
58
4.91010
210–2 - 80
5.6105
50
21011
310–2 – 140 (14)
5.8103
480
3.91010
3.5 - 8103
7.2104
430
3109
2.510–1 - 500
1.6105
414
1 - 2000
1.21010
1.6105
36
< 21013
210–1 - 900
8.9103
330
8.7106
110–3 - 1.5
1.6105
290
1.3109
310–2 - 140
3105
30
1109
110–5-110–2 (5 10–4)
4.2103
290
1.1108
110–2 – 20 (1)
1.6105
210
7.5108
510–2 - 100
2.3104
200
9.4107
510–3 - 10
1.6105
109
140
410–2 - 80
1.6105
90
7109
110–1 - 220
6.2104
600
10 - 10,000
61011
1.7106
–3 12-14 May, 2008
1010 SERENA-HEWG
68 meeting, Santa
810Fe,
- 40
3.8105
Neutral Zenith
Column density
cm–2
Neutral scale
Height
km
Range of Ion density
at 400 km cm–3
510–5 - 2.4
110–4 - 70
210–4 - 4
110–4 - 70
210–6 - 810–2
410–7 -10
110–7 - 610–2
110–5 - 7
210–3 - 440
110–5 - 16
2.510–4 - 72
310–5 - 32
2.510–7-410–2
610–6 - 3
210–10 - 110–4
510–6 - 810–2
110–3 - 220
410–5 - 8
110–5 - 1.610–1
210–5 - 4
310–4 - 120
110–7 - 410–2
Sc. Obj:6
Neutral density asymmetries
The measurements of the spatial distributions of the
neutrals as well as ions are a possible way to
understand the ejection processes that lead to these
distributions and to have information about the
history of the particles during their trajectories.
Moreover, asymmetries induced by strong thermal
variations, between different latitudes, day/night,
dawn/dusk sides and perihelion/aphelion are
expected in the Hermean exospheric density.
STROFIO will observe these asymmetries.
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj:1
Sodium observations
variability
(Potter et al., 2002)
tail
(Potter et al., 1999)
Dawn-dusk
asymmetries (Schleicher et al. A&A, 2004)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of scientific requirements (1)
Signal
Angular/spatial
Energy
Useful
Scientific
Intensity
Major
coverage
Time
Observable
Energy
associated
Topic
@ 400
Components
Angular
resolution
region
resolution
observations
km
resolution
H, He, O, Na,
1. Chemical
5
–3
K,
10 cm
and elemental
< 1 eV
Whole
Ca, H2, OH,
Not req.
min req.
composition of
Not req
Not req
planet
Mg, Si, others
101 cm–3
the exosphere
…
H, He, O, Na,
6a. Neutral gas
5
–3
K,
10 cm
density
< 1 eV
Whole
Ca, H2, OH,
min req.
T<15 m
asymmetries
Not req.
Not req.
planet
Mg, Si, others
101 cm–3
Latitude
…
6b, c. Neutral
H, He, O, Na,
5
–3
gas density
K,
10 cm
< 1 eV
Whole
asymmetries
Ca, H2, OH,
min req.
T>orbit
Not req.
Not req.
planet
Day/night
Mg, Si, others
101 cm–3
Dawn/dusk
…
6d, e. Neutral
H, He, O, Na,
Altitude
5
–3
gas density
K,
10 cm
< 1 eV
Whole
density
asymmetries
Ca, H2, OH,
Not req.
min req.
Not req.
Not req.
planet
profiles
Altitude
Mg, Si, others
101 cm–3
variations
LT
…
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of instrument performances (1)
Scientific
Topic
1. Chemical
and
elemental
composition
of the
exosphere
6a. Neutral
gas density
asymmetries
Latitude
6b, c.
Neutral gas
density
asymmetries
Day/night
Dawn/dusk
6d, e.
Neutral gas
density
asymmetries
Altitude
LT
Geometrical
factor
Energy
Energy
resolution
Mass
resolution
FOV
Time
SERENA
Angular
resolution
units
resolution
10–6
GF10–1
< 1 eV
NA
>60
NA
10–6
GF10–1
cm2 sr
< 1 eV
NA
>60
NA
T<15 m STROFIO
10–6
GF10–1
cm2 sr
< 1 eV
NA
>60
NA
T>orbit STROFIO
10–6
GF10–1
cm2 sr
< 1 eV
NA
>60
NA
NA
NA
STROFIO
Synergies with
other BC
instruments
MPO/PHEBUS
STROFIO MPO/PHEBUS
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj:2
Exo-ionosphere composition
Ions of planetary origin have been
observed by MESSENGER in the
magnetospheric tail.
They are likely generated in the dayside
hemisphere due to photoionisation and
ion-sputtering processes.
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj:2
Neutral
Species
H
He
Li
C
N
O
Ne
Na
Mg
Al
Si
S
Cl
Ar
K
Ca
Fe
Ni
Kr
Xe
H2
OH
Expected range of the ion/neutral densities in
Mercury's close-to-planet environment
Neutral density Range
Photo(observed)
ionization
at 400 km
lifetime
–3
cm
s
9
–2
1160 (1330)
310
410 -200 (20)
5.1106
500 (330)
31011
5 - 2104 (2600)
1.7106
190
< 8.4107
810–4 - 4
4.1102
96
11011
310–1 - 1600
2.6104
83
51010
110–1 - 500
5105
72 (83)
< 31011
310–1 – 1600 (160)
5105
58
4.91010
210–2 - 80
5.6105
50
21011
310–2 – 140 (14)
5.8103
480
3.91010
3.5 - 8103
7.2104
430
3109
2.510–1 - 500
1.6105
414
1 - 2000
1.21010
1.6105
36
< 21013
210–1 - 900
8.9103
330
8.7106
110–3 - 1.5
1.6105
290
1.3109
310–2 - 140
3105
30
1109
110–5-110–2 (5 10–4)
4.2103
290
1.1108
110–2 – 20 (1)
1.6105
210
7.5108
510–2 - 100
2.3104
200
9.4107
510–3 - 10
1.6105
109
140
410–2 - 80
1.6105
90
7109
110–1 - 220
6.2104
600
10 - 10,000
61011
1.7106
–3 12-14 May, 2008
Fe,
1010 SERENA-HEWG
68 meeting, Santa
810
- 40
3.8105
Neutral Zenith
Column density
cm–2
Neutral scale
Height
km
Range of Ion density
at 400 km cm–3
510–5 - 2.4
110–4 - 70
210–4 - 4
110–4 - 70
210–6 - 810–2
410–7 -10
110–7 - 610–2
110–5 - 7
210–3 - 440
110–5 - 16
2.510–4 - 72
310–5 - 32
2.510–7-410–2
610–6 - 3
210–10 - 110–4
510–6 - 810–2
110–3 - 220
410–5 - 8
110–5 - 1.610–1
210–5 - 4
310–4 - 120
110–7 - 410–2
Sc. Obj:2
Exo-ionosphere distribution
Na+ distribution model by Leblanc foresees strong
asimmetries
(Leblanc et al., 2004)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of scientific
requirements (2)
Scientific
Topic
2a. Exoionosphere
composition
2b. Exoionosphere
spatial
distribution
Signal
Intensity
@ 400 km
102 cm–3
min req. 1
cm–3
Energy
Energy
resolution
>0 eV
Not req.
102 cm–3
>0 eV
min req. 1
E/E <30%
cm–3
Major
Components
Angular/spati
al coverage
Angular
resolution
Time
resolution
Observable
region
H+, He+, Na+,
O+, K+, others
…
Not req.
Not req.
Whole planet
H+, He+, Na+,
O+, K+, others
…
Not req.
T<2 m
Whole planet
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of instrument
performances (2)
Scientific
Topic
2a. Exoionosphere
composition
2b. Exoionosphere
spatial
distribution
Geometrical
factor
Energy
Energy
resolution
Mass
resolution
FOV
Time
SERENA
Angular
resolution
units
resolution
10–1 cm2 sr
>1 eV
NA
>50
NA
NA
PICAM
10–1 cm2 sr
>1 eV
E/E <
>50
NA
T<15 m
PICAM
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Synergies with
other BC
instruments
Sc. Obj: 3
Surface release processes
Different release processes can have
different efficiencies as a function of latitude
and longitude/LT at Mercury due to surface
compositions and mineralogy togheter with
external conditions, as solar irradiance or
plasma precipitation. Among the release
processes the ion-sputtering is particularly
intriguing since the involved energies induce
escape from the planet, with possible
implication on its evolution.
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj: 3
Particle release processes
TD
PSD
IS
MIV
(Environment Simulation Tool (EST) at IFSI)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj: 3
Energy distribution of sputtered particles
by Wurz et al, SERENA Meeting in Pejo, 2006
H escape
O escape
Ca escape
Fe escape
STROFIO ELENA
Fe Ca O
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
H
Why we require detection of neutrals
at energies >10 eV
(EST@IFSI)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj: 3
Ion-sputtering process
ELENA will map the location of the
sputtering process on the surface and will
image of the surface loss rate
Surface sputtered signal
obtainable by ELENA
when MPO pericentre is in
the day side
(Mura et al, PSS, 2005)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj: 3
Impulsive event (meteoroid 0.1 m)
Frequency
~
2 events/day
(Marchi et al, A&A, 2005)
Duration
Amplitude
~ 10-30 min
~ 2000 km
(Mangano et al., PSS, 2007)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Intensifications, durations and spatial
dimensions of a 10 cm MIV exosphere
METEORITE OF 10 cm
Altitude:
Species
Intensification I
Duration Δt
Extension d
Altitude:
Species
Intensification I
Duration Δt
Extension d
Na
/ d
~3n
0 d
300 n
-d
0º n
Na(*)
-d
-n
Mg
Al
Si
S
O
~ 103
~ 103
103
10
> 10
1900
2000
~2500
800
~900
40º
50º
45º
25º
30º
Mg
Al
Si
S(*)
O
< 102
< 102
102
-
< 10
2700
~ 2200
~ 3200
-
1200
100º
70º
80º
20º
20º
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
K(*)
-d
-n
K(*)
-d
-n
Ca
< 104
3500
50º
Ca
> 102
3500
90º
Probability to detect 10 cm MIV
exosphere
average
1500km
400km
Species
Duration
1 day
1 month
Na
/
/
/
/
d
n
d
n
Mg
Al
Si
S
O
15.5%
21%
21%
5%
6.8%
99.3%
99.9%
99.9%
1 day
/ d
/ n
20%
1 month
/ d
/ n
99.8%
1 day
/ d
/ n
1 month
/ d
/ n
22.5%
77.8% 87.8%
K
/
/
/
/
d
n
d
n
/ d
/ n
Ca
30%
99.9%
27%
/
4.7%
99.9%
99.9%
/
76.3%
17.7%
21.7%
24%
0-5%
5.7%
/ d
44%
/ n
99.5%
99.9%
99.9%
077.8%
82%
/ d
/ n
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
/ d
/ n
58%
99.9%
99.9%
Summary of scientific requirements (3)
Scientific
Topic
3a. Localized
surface
emissivity
induced
by
ion- sputtering
3b. Average
SW sputtering
emission rate
3c. Surface
vaporization
micrometeorit
e impact
3d. PSD
Energy
Angular/spat
Useful
Signal
Energy
Major
ial coverage
Time
Observabl associated
Intensity
resolutio Components
Angular
resolution e region observation
@ 400 km
n
resolution
s
1H, Mg, Si, O,
Plasma
8
hundreds
Up to10
Na, K, Ca,
precipitation
Order of RM
Mainly
2
–1
(cm s sr)
eV
others…
(4a)
on the surface
dayside
min req.
min req.
min req.
Surface
T< 3 m
middles < 50 km
6
2
20 eV
10 (cm s
light/heavy
composition,
latitude
–1
sr)
mass
mineralogy
v/v <
discrimination
and structure
10%
1H, Mg, Si, O,
8
Up to10
hundreds
Na, K, Ca,
Mainly
2
–1
Order of RM
eV
(cm s sr)
others…
dayside
min req.
on the surface T <10 m
min req.
min req.
middle20 eV
106 (cm2 s
light/heavy
s < 100 km
latitude
sr)–1
mass
v/v <
discrimination
10%
105 cm–3
min req.
101 cm–3
< 2 eV Mg, Si, O, Na,
Not req. K, Ca, others…
Not req.
T< 5 m
Whole
planet
105 cm–3
min req.
101 cm–3
< 1 eV
Not req.
Not req.
T <10 m
Dayside
H, He, O, Na,
K, others…
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of instrument performances (3)
Geometrical
factor
Energy
Energy
resolution
3a. Surface
emissivity
induced by
ion- sputtering
10–5
cm2 sr
<20 -100s
eV v/v <
10%
3b. SW
sputtering
emission rate
10–5
cm2 sr
<20 -100s
eV v/v <
10%
Scientific
Topic
3c. Surface
10–6
vaporization
micrometeorite GF10–1
impact
10–6
3d. PSD
GF10–1
FOV
Synergies with
Time
SERENA
Angular
other BC
resolution units
resolution
instruments
o
o
2 x60
Hydrogen/
MPO/MIXS
ELENA
(nadir
heavy
MPO/MERTIS
T< 3 m STROFIO
centred)
particles
MPO/Simbio
MIPA
o
discrimination
Sys
 < 8
Hydrogen/
2ox60o
heavy
ELENA
T< 3 m
o
particles
STROFIO
 < 15
discrimination
Mass
resolution
< 1 eV
NA
>60
NA
T< 5 m STROFIO
< 1 eV
NA
>60
NA
T <10 m STROFIO MPO/PHEBUS
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
MMO/MDM
Sc. Obj: 4
SW precipitation
The SW ions (at energy
about 1 keV) entering in the
magnetosphere partially
reach the planet surface
causing ion sputtering,
hence producing neutral
atoms and ions.
MIPA will monitor the SW
precipitation.
(Massetti et al., 2003)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj: 4
Planetary ions precipitating from the
magnetosphere
 Planetary heavy ions precipitate toward the planet in the day side
high latitudes and in the night side mid/low latitudes
The precipitating
planetary heavy ion
fluxes are expected to
be lower than the
precipitating solar
wind fluxes. Thus,
they will be observed
by MIPA and PICAM
in the night side
where the solar wind
contribution is
expected to be
negligible.
(Seki et al., 2006)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
(Delcourt et al., 2003)
Sc. Obj: 4
Loss cone angle
The particle precipitates when
V///Vn is high (i.e. the pitch angle
is lower than the loss cone
angle) (Nilsson et al. 1997)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of scientific
requirements (4)
Scientific
Topic
4a. Plasma
precipitation
rate:
SW
4b. Plasma
precipitation
rate:
Heavy ions
Signal
Angular/spatial
Energy
Useful
Intensity
Major
coverage
Time
Observable
Energy
associated
@ 400
Components
Angular
resolution
region
resolution
observations
km
resolution
Magnetic
108 (cm2
0.5-10
–1
2 in the orbit
field
s sr)
keV
Mainly
+
Mainly H
plane
Fluxes and
min req.
T< 5 m
dayside
E/E
6
2
o
fields from
10 (cm
 < 25
<30%
–1
different v.p.
s sr)
Magnetic
106(cm2
0.5-10
–1
2 in the orbit
field
s sr)
keV
Mainly Na+,
Whole
plane
Fluxes and
min req.
T< 5 m
O+
planet
E/E
5
2
o
fields from
10 (cm s
 < 25
<30%
–1
different v.p.
sr)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of instrument
performances (4)
Scientific
Topic
4a. Plasma
precipitation
rate
SW
4b. Plasma
precipitation
rate
Heavy ions
Geometrical
factor
Energy
Energy
resolution
10–6
GF10–4
cm2 sr
0.5-15
keV
E/E
<30%
10–5
cm2 sr
0.5-15
keV
keV
E/E
<30%
FOV
Synergies with
Time
SERENA
Angular
other BC
resolution
units
resolution
instruments
o
o
5 x180
FOV in
H
MPO/MERMAG
identification the orbit T< 5 m
MMO/MPPE
MIPA
+
plane
MMO/MGF
o
 < 25
5ox180o
FOV in
MPO/MERMAG
MIPA
the orbit T< 5 m
>10
MMO/MPPE
PICAM
plane
MMO/MGF
o
 < 25
Mass
resolution
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj: 5
Loss rate from Hermean environment
The high-energy neutral products of the release processes as
well as the charge-exchange ENA, are mainly created close to
the surface and carried outward of the planetary environment
due to their high velocity that exceeds the escape velocity
(vesc= 4 km/s). Directional neutral measurements by ELENA
will contribute in evaluating the mass loss from the Hermean
environment.
(Mura et al., 2006)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj: 5
Loss rate from Hermean environment
The ions produced at thermal energies are
energised and become part of the magnetospheric
ion populations. Part of the magnetospheric plasma
is eventually lost to the SW. PICAM high energy
resolution will allow such an investigation.
(Delcourt et al., 2003)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of scientific requirements (5)
Scientific
Topic
5a. Particle
loss rate from
Mercury’s
environment
SW
sputtering
Signal
Angular/spatial
Energy
Useful
Intensity
Major
coverage
Time
Observable
Energy
associated
@ 400
Components
Angular
resolution
region
resolution
observations
km
resolution
1H, Mg, Si, O,
8
Up to10 hundreds
Na, K, Ca,
(cm2 s)–1
eV
Mainly
Plasma
others…
–1
Half planet
min
sr)
dayside
Not req.
precipitation
min req.
min req. req.>20
s < 100 km
middlelight/heavy
(4a)
eV
106 (cm2
latitude
mass
s)–1 sr)–1
v/v <
discrimination
50%
107
mainly H,
1/(cm2 s 500 eV-10
Up to hundreds
may be,
Mainly
c-e ENA
sr)
keV
km above the
planetary
Not req.
close to
from wider
min req.
planet
v/v <
5
major
horizon
FOV
5 10
50%
 < 8o
2
components
1/(cm s
sr)
5b. Particle
loss rate from
Mercury’s
environment
Exospheric
chargeexchange
5c. Particle
107(cm2 500 eV-10
loss rate from
s)–1 sr)–1
keV
Mercury’s
Mainly Na+,
min req.
 < 25o
T< 5 m
+
environment
O
E/E
5
2
10 (cm
Loss of
<30%
s)–1 sr)–1
planetary ions
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Whole
planet
Magnetic
field
Summary of instrument performances (5)
Scientific
Topic
5a. Particle
loss rate
from
Mercury’s
environment
SW
sputtering
5b. Particle
loss rate
from
Mercury’s
environment
Exospheric
chargeexchange
5c. Loss of
planetary
ions
Geometrical
factor
Energy
Energy
resolution
Mass
resolution
FOV
SERENA
Time
Angular
units
resolution
resolution
10–5
cm2 sr
Hydrogen/
<20 -100s
heavy
eV v/v <
particles
50%
discrimination
2ox60o
(nadir
centred)
 < 15o
NA
ELENA
10–5
cm2 sr
500 eV-5
Hydrogen/
keV
heavy
particles
v/v <
discrimination
50%
2ox20o
(toward
horizon)
 < 8o
NA
ELENA
–1
10
cm2 sr
500 eV-10
keV
E/E <
30%
>50
Hemispheric
FOV
T< 5 m
o
 < 25
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Synergies with
other BC
instruments
MMO/MPPE
PICAM
MPO/MERMAG
MIPA
Summary of ELENA scientific
performances
Energy range
<0.02- 5 keV (mass dependent)
Velocity resolution v/v
Down to 15%
Viewing angle
2ox76o
Nominal angular resolution
2ox2o
Mass resolution M/M
H and heavy species
Optimal temporal resolution
18 s
Geometric factor G
1. 10–5 cm2 sr
Integral Geometric factor
4 10–4 cm2 sr
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of STROFIO scientific
performances
Energy range
< eV
Viewing angle [deg]
20o x 20o
Mass resolution M/M
60
Mass range
1-64 dalton (AMU)
Sensitivity
0.14 (counts/s)/ (particles/cm3)
Temporal resolution
10 s
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of MIPA scientific
performances
Energy range
10 eV – 15 keV
Energy resolution E/E
7%
Viewing angle
9o x 180o
Angular
(FWHM)
resolution 4.5° x 22.5° (inherent 4.5° x 8°)
Mass range, amu
1 – 50
Mass resolution, M/M
~5
Time resolution, sec
8 s, Full Azimuth – Energy cycle (8A x 32E)
Efficiency, e
1 – 10% (adjustable to decrease GF)
Geometrical factor
1.8·10-3 cm2 sr eV/eV w/o efficiency
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Summary of PICAM scientific
performances
Energy range
1 eV - 3 keV
Energy resolution E/E
7%
Viewing angle
3-D, 2
Angular resolution
~22.5o
Mass resolution M/M
>50
Mass range
1 ... ~132 AMU (Xe)
Time resolution
1 s ... 32 s
Geometric factor G = S
3.4 x 10–3 cm2 sr
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
SERENA new webpage: Home
http://www.ifsi-roma.inaf.it/enagroup/serena/index.php?categoryid=1
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
SERENA new web site: Science
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
SERENA new web site: Team
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
SERENA new web site: Resources
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
SERENA Science team and
thematic WGs
The SERENA science team is involved in the
Hermean Environment WG. It has recently
coordinated and participated to the paper on HE
for the PSS special issue.
It has participated also to the Surface and
Composition paper in the same special issue
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Thank you
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
BepiColombo key questions
Which are the composition, the origin
and the dynamics of Mercury’s
exosphere and polar deposits?
Which are the structure and the
dynamics of Mercury’s magnetosphere ?
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj:1
Sodium and Potassium observations
(Killen et al. SSR, 2007)
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Sc. Obj:1
Oxygen
The small amount of observed atmospheric
oxygen relative (<4. 104 cm-3) relative to
the surface stoichiometry (≈50%) may
indicate that atmospheric oxygen is bound
in molecules, or it may indicate inefficient
release (Morgan and Killen, 1997), or it may
efficiently charge exchange with solar wind
and magnetospheric protons.
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008
Calcium
The neutral Calcium was
observed by Bida et al.
(2000).
It is likely that Ca is
released in the molecular
form, possibly as CaO. If so,
CaO could be dissociated in
the atmosphere by Ly
photons, giving the Ca atom
excess energy as observed
(Killen et al., 2005).
SERENA-HEWG meeting, Santa Fe, 12-14 May, 2008