Can the X(3872) be a 1^{++} four-quark state?

We use QCD spectral sum rules to test the nature of the meson X(3872), assumed to be an exotic four-quark (c\bar{c}q\bar{q}) state with J^{PC}=1^{++}. For definiteness, we work with the current proposed recently by Maiani et al [1], at leading order in \alpha_s, consider the contributions of higher dimension condensates and keep terms which are linear in the light quark mass m_q. We find M_X=(3925+- 127) MeV which is compatible, within the errors, with he experimental candidate X(3872), while the SU(3) breaking-terms lead to an unusual mass-splitting M_{X^{s}}-M_X=- (61+-30) MeV. The mass-difference between the neutral states due to isospin violation of about (2.6-3.9) MeV is much smaller than the value (8+-3) MeV proposed in [1]. For the b-quark, we predict M_{X_b}= (10144+-106) MeV for the X_b(b\bar{b}q \bar{q}), which is much below the {\bar B}B* threshold in contrast to the {\bar B}B* molecule prediction [2], and for the X_b^s(b\bar{b}s \bar{s}), a mass-splitting M_{X^s_{b}}-M_{X_b}=-(121+-182) MeV. Our analysis also indicates that the mass-splitting between the ground state and the radial excitation of about (225~250) MeV is much smaller than in the case of ordinary mesons and is (within the errors) flavour-independent. We also extract the decay constants, analogous to f_\pi, of such mesons, which are useful for further studies of their leptonic and hadronic decay widths. The uncertainties of our estimates are mainly due to the ones from the c and b quark masses.Comment: 16 pages, 10 figures. Version to appear in Phys. Rev.

Kajian Peranan Tanaman Hedgerow Dalam Sistem USAhatani Konservasi Di Lahan Kering Terhadap Sifat Fisik Tanah

Study the Role of Hedgerow Plants in Conservation of Dryland Farming Systems on Soil Physical Properties. To determine the effect of infiltration rate and soil physical properties, a study was conducted in the village Oebola, Fatuleu, Kupang district, from November 2008 to June 2009. The experiment was designed in Randomized Block Design (RBD), with four treatments and three replications. The treatments were three types of fencing plants in alley cropping systems i.e. white leadtree (Leucaena leucocephala), hummingbird tree (Sesbania grandiflora syn. Aeschynomene grandiflora), gliricidia (Gliricidia sepium), and the treatment without fencing plants as the control. The parameters observed were organic matter content, bulk density, field water content, maximum water content, aggregate stability, and infiltration rate. Data were analyzed statistically using the F-test and was continued with Duncan test if there was a difference among the treatments tested. The result showed that in the three fencing plants tested, gliricidia gave the best effect in the terms of organic matter content, field water content, maximum water content, and infiltration rate while bulk density of these three plants relatively performed the similar influence

Kajian Cekaman Kekeringan Dan Dosis Pupuk Nitrogen Terhadap Hasil Padi Gogo (Oryza Sativa L)

The Study of the Droght Stress and The Nitrogen Fertilizer Doses For the Plant Gogo Produce. The research had taken place in glasses house BPTP Naibonat Kupang from Junni to October 2008. The aims of the research is to know the influences of the value of the drought sress and the nitrogen of Fertilizer doses for the product of Rice plant Gogo. The research was done by using Randomized Complete Design factorial research which consist of two factors which is used without barren, the droght stess 21 -25 HST, 76 -80 HST and 111 – 115 HST. The secont factor is Nitrogen fertilizer doses which used and without nitrogen fertilizer, 45 kg N/ha, 90 kg N/ha and 135 kg N/ha, with 3 replication. The variabel which observed is the number of plant seed, the panicle number the qualiy of one thousand seeds, the qualiity of the seeds, and harvest index per plantation. The result of the research souws that the effect of drounght and doses nitrogen fertilazer of Riceland field for the fariabel which observed is seed number, the seed quality and the quality of the seed per plantation. The treatmen of the second droht stress (C2) with nitrogen fertilizer doses 90 kg/ha (N2) gives the average seed quality per plantation, whichis higher than the onther tretment