Inner main belt

The inner main belt is dynamically limited in semi-major axis by the 3J:-1A mean-motion resonance at high a (Zappalá et al. 1995).  The 7J:-2A mean-motion resonance is sometimes used by some authors
as the boundary between the inner main belt at high inclination and the region of the Hungaria asteroids.   In this work we will just use the upper limit in a given by the 3J:-1A mean-motion resonance. The linear secular resonance g-g6 separates the low-inclined asteroid region from the highly inclined area, dominated by the Phocaea family (see Carruba 2009b, 2010a for a discussion of the local families groups and dynamics).  The Phocaea family is located in a stable island limited by the 7J:-2A and 3J:-1A in semi-major axis, and by the g-g6 and g-g5 secular resonances in inclination (Knezevic and Milani 2003).  We found 2402 objects that have proper elements and frequencies, SDSS-MOC (a*,i-z) colors, WISE geometric albedo data in the inner main belt, and reasonable errors, according to our criteria.   The inner main belt is slightly dominated by S-complex asteroids, but with a significant minority of CX-complex bodies.  V-type asteroids are mostly concentrated in the Vesta family, but with a significant population outside the dynamical group (see also Carruba et al. 2005).
inner density
inner aiz
inner pv
Contour plot of the number density of asteroids in the proper element sample. 
Superimposed, we display the orbital location of asteroids of families in the CX-complex (plus signs) and S-complex (circles).
An (a*,i-z) projection of inner main belt asteroids in the in our multi-domain sample.
A histogram of number frequency values ni/NTot as a function of geometric albedo pV for inner main belt  asteroids in our multi-domain sample.

First halo
member
dmd [m/s]
Number of
members
Spectral
complex
Number of
SDSS-MOC4
interlopers
Number of
albedo
interlopers
(298) Baptistina: (4691)
250
56
CX
2
47
(4) Vesta: (2011)
275
161
S(V)
46
26
(163) Erigone: (9566)
400
57
CX
0
1
(20) Massalia: (10102)
235
33
S
6
9
(44) Nysa/Mildred/Polana: (1768)
280
147
CX
0
1
(27) Euterpe: (5444)
335
9
S
2
1
(25) Phocaea: (3322)
> 800
82
S
27
16