Papers by Fargiza A. M. Mulki
Epj Web of Conferences, 2020
In this paper, we reconstruct matter power spectrum of a cosmological model in which coupled scal... more In this paper, we reconstruct matter power spectrum of a cosmological model in which coupled scalar field acts as dark energy. The coupled scalar field (CSF) dark energy we propose here is a generalized model of quintessence, k-essence or phantom coupled to dark matter (nonbaryonic matter) via a coupling constant. The existence of coupling between dark energy and matter allows energy to transfer between them, which may give rise to different observational signatures, especially at perturbation level, including matter power spectrum. In this work, through analytical exploration we studied that possible signature in matter power spectrum that maybe induced by this mode.
Journal of physics, Nov 1, 2016
Prominence is a hot gas that consists of electrically charged particles, which is propelled outwa... more Prominence is a hot gas that consists of electrically charged particles, which is propelled outward Solar surface. It can happen when the activity of sunspot rising up. Groundbased observation of prominence is rather difficult due to the brightness of the Sun, which it needs appropriate method. During total solar eclipse (TSE), prominence is easier to observe. In Ternate, Maluku islands (0°4632.0"N 127°2305.7"E), we observed solar prominence in visual and infrared spectra performed by using regular-DSLR camera for visual wavelength and modified-DSLR (IR-cut filter removal) for infrared wavelength, respectively. Next, we calculated the length of prominence from TSE images, and found that the real minimum length of prominence in red is 1.05 times longer than green and blue ones. And, the real maximum length of prominence is 1.08 times longer than blue and 1.04 times longer than green. The intensity of red is brighter 1.37 times to green and 1.23 times to blue. The causes of the results due to the different temperatures of the prominences and the radiation from H-alpha emission. We succeeded to observe directly the prominence with simple cameras and measured its length and brightness.
SSRN Electronic Journal
We propose noncanonical domain walls as a new dark energy model inspired by grand unified theorie... more We propose noncanonical domain walls as a new dark energy model inspired by grand unified theories (GUTs). We investigate the cosmic dynamics and discover that the domain walls act as either dark energy or dark matter at different times, depending on the velocity v in the observer's comoving frame. We find a single stable solution to the dynamics, i.e., only freezing (v = 0) noncanonical domain walls can enter the phantom zone without having to experience ghost field instability. This means that the solution has an equation of state (EoS) w dw < −1 without having to possess negative kinetic energy. These domain walls give rise to a late-time cosmic acceleration starting from z ≈ 0.8, resulting in w dw = −1.5 and w ef f = −1.03 today. We learn that the EoS of the noncanonical domain walls is independent of the potential form. We also investigate the perturbation dynamics following the model. Our simulations show that compared to ΛCDM, the amplitude of the dark matter power spectrum in the noncanonical domain wall model is lower, while the CMB power spectrum is shifted slightly to lower l multipoles. The proposed model gives a smaller σ 8 compared to that of ΛCDM. 4 Inhomogeneous universe with noncanonical domain walls 11 4.1 Analytical study 11 4.1.1 Matter perturbation 15 4.1.2 Growth rate of large scale structures 16 4.
EPJ Web of Conferences, 2020
In this paper, we reconstruct matter power spectrum of a cosmological model in which coupled scal... more In this paper, we reconstruct matter power spectrum of a cosmological model in which coupled scalar field acts as dark energy. The coupled scalar field (CSF) dark energy we propose here is a generalized model of quintessence, k-essence or phantom coupled to dark matter (non-baryonic matter) via a coupling constant. The existence of coupling between dark energy and matter allows energy to transfer between them, which may give rise to different observational signatures, especially at perturbation level, including matter power spectrum. In this work, through analytical exploration we studied that possible signature in matter power spectrum that maybe induced by this mode.
Journal of Physics: Conference Series, 2019
A universe containing a coupled scalar field would have different dynamical evolution compared to... more A universe containing a coupled scalar field would have different dynamical evolution compared to uncoupled cases. Significant differences are expected to emerge during matter dominated era, where scalar field density mimics how matter density evolves, by becoming subdominant. Analysis of the dynamics was investigated both analytically and numerically through phase plane method, and we obtained two attractor solutions which are compatible to a late time cosmic acceleration as the ending of matter dominated era. Ordinary scalar field triggers an acceleration with stable attractor solution which converges to ωϕ = ωeff ≈ −1. Whereas, phantom scalar field allows negative values for its own energy (ωeff ˂ −1 and Ωϕ ˂ 0); however this is not stable, therefore it will be caught by attractor solution which is stable to ωϕ = ωeff ≈ −1. In addition, we found cosmological parameters generated from both analytical and numerical calculations, i.e. ωϕ , Ωϕ and ωeff , by assuming a flat universe. ...
Journal of Physics: Conference Series, 2019
We performed an investigation of the possibility of constraining the dark energy models such as w... more We performed an investigation of the possibility of constraining the dark energy models such as w-cold dark matter, holographic dark energy, and Ricci dark energy, using a special type of Einstein ring system, called as double-source plane (DSP) lensing system. We found that DSP lensing system only gives a good constraint of the model parameters. We also found that the method highly complimentary to cosmic microwave background measurement for each model.
Stability and electronic properties of defective single walled carbon nanotubes (CNTs)
Journal of Physics: Conference Series, 2016
Background: Stenochlaena palustris (kelakai) is one of the medicinal plants that has been used by... more Background: Stenochlaena palustris (kelakai) is one of the medicinal plants that has been used by Dayak ethnic society as an alternative medicine to treat anemia. An earlier study showed that kelakai extract is associated with an increase in white rat's hemoglobin (Hb) level. The purpose of this study was to determine the effect of a local based supplementary food on increasing Hb among pregnant women in Central Kalimantan. Subjects and Method: This was a quasi-experiment conducted in Palangkaraya, Central Kalimantan. A sample of 71 pregnant women was selected for this study and divided into two groups: 29 in the kelakai group and 42 in the control group. The dependent variable was Hb level. The independent variable was local based supplementary food with kelakai. The data were analyzed by t-test. Results: Boiling kelakai vegetable yielded 0.075mg/kg Fe in one minute and 0.036 mg/kg in five minutes. Raw kelakai leaf contained 0.384mg/kg Fe. Pregnant women who consumed kelakai (mean= 10.3; SD= 0.88 g/dl) had higher Hb level than those who did not consume kelakai (mean= 9.6; SD= 0.84 g/dl). Pregnant women had higher Hb level after consumption of local based supplementary food (mean=10.32; SD=0.88 g/dl) than before consumption (mean=9.63; SD=1.01 g/dl). Conclusion: Consumption of local based supplementary food is effective to increase hemoglobin level among pregnant women.
Journal of Physics: Conference Series, 2016
Prominence is a hot gas that consists of electrically charged particles, which is propelled outwa... more Prominence is a hot gas that consists of electrically charged particles, which is propelled outward Solar surface. It can happen when the activity of sunspot rising up. Groundbased observation of prominence is rather difficult due to the brightness of the Sun, which it needs appropriate method. During total solar eclipse (TSE), prominence is easier to observe. In Ternate, Maluku islands (0°4632.0"N 127°2305.7"E), we observed solar prominence in visual and infrared spectra performed by using regular-DSLR camera for visual wavelength and modified-DSLR (IR-cut filter removal) for infrared wavelength, respectively. Next, we calculated the length of prominence from TSE images, and found that the real minimum length of prominence in red is 1.05 times longer than green and blue ones. And, the real maximum length of prominence is 1.08 times longer than blue and 1.04 times longer than green. The intensity of red is brighter 1.37 times to green and 1.23 times to blue. The causes of the results due to the different temperatures of the prominences and the radiation from H-alpha emission. We succeeded to observe directly the prominence with simple cameras and measured its length and brightness.
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Papers by Fargiza A. M. Mulki