where D = 3 A − 3 and h αβ K is the norm of the Jacobi polynomial P αβ K ( z ). The one-body density contains information regarding one particle aspect of the bosonic system. Although it is not directly measurable but in the interferometry experiment one can indirectly explore it $^{6,7}$. In Fig.1 we present calculated one-body density as a function of the distance from the trap centre for a repulsive interaction corresponding to a$_{s}$ = .00433 o.u. for 10000 $^{87}$Rb atoms in the JILA trap$^{25}$. In our calculation, length and energy are measured in oscillator units (o.u.) of length ( a$_{ho}$ = √ ℏ mω ) and energy ( ℏ ω ) respectively. For comparison, we also include the mean-field results. The effect of interaction is revealed by the deviation from the Gaussian profile. To explore the effect of interaction, we also calculate one-body density for a smaller a$_{s}$ value viz. , a$_{s}$ = 2 . 09 × 10 − 4 o.u. for the same number of particles. Since the trapped condensate is always stable even for a large A , we see appreciable changes in R$_{1}$ ( ⃗ r$_{k}$ ) as a$_{s}$ decreases. For small a$_{s}$ , the density distribution is sharper as the correlations induced by the interactions are weak, while for the larger a$_{s}$ , the peak is flatter with a larger width. In Fig. 2 we present calculated one-body density for an attractive BEC with a$_{s}$ = − 1 . 836 × 10 − 4 o.u for different number of $^{85}$Rb atoms in the JILA trap $^{26}$. The effective interaction parameter is λ = A | a$_{s}$ | /a$_{ho}$ . For A = 100, λ is small and the system exhibits weak one-body density which extends to the trap size. Increasing A gradually, the net effective attraction becomes strong and the density becomes sharply peaked at a smaller distance. Taking the Fourier transform of R$_{1}$ ( ⃗ r$_{k}$ ), we obtain the one-body momentum distribution. One-body density is an abstract concept. However, its fourier transform gives the experi- mentally measurable quantity, the momentum distribution. In Fig. 3, we plot our results for repulsive interactions. It evolves from a Gaussian in the noninteracting limit to a curve 7 R$_{1}$ ( ⃗ r$_{k}$ ) = $^{√$_{2}$}$∫ ∞ 0 ∫ 1 − 1 2 α [ 1 π 3 / 2 Γ (( D − 3) / 2) Γ (( D 6) / 2) ] [ ζ$_{0}$ ( r $^{′}$)] 2 ∑ KK ′ χ$_{K}$$_{0}$ ( r $^{′}$) χ$_{K}$ ′ $_{0}$( r $^{′}$)( f$_{Kl}$f$_{K}$ ′ $_{l}$) − $^{1}$( h αβ K h αβ K ′ ) − 1 / $^{2}$P αβ K ( z ) P αβ K ′ ( z ) r ′ D − 4 √ 1 + z 2 (√ 1 − z 2 ) D − 8 ( √ r ′ 2 + 2 r 2 k ) − ( D − 1) dr $^{′}$dz, (8)