can't manage to use costmap_2d individually

Hello, i can create map with gmapping and hector_slam. since i dont have a robot system (just laser scanner) i'm just trying to use costmap_2d individually so i created a launch file (based on example.launch in costmap_2d launch directory) while i was running gmapping (with laser scan matcher), in another terminal i run, "rosrun map_server map_server mymap.yaml" ...then my costmap.launch, didnt gave any error, but in rviz nothing has changed. what am i missing? *note: i created launch directory in laser_scan_matcher in the first place so i continue to use that directory for creating new launch and yaml files for my case. my costmap.launch file: my params.yaml file: global_frame: /map robot_base_frame: base_link update_frequency: 5.0 publish_frequency: 1.0 publish_voxel_map: true static_map: false map_type: voxel origin_z: 0.0 z_resolution: 0.2 z_voxels: 10 unknown_threshold: 10 mark_threshold: 0 transform_tolerance: 0.3 obstacle_range: 2.5 max_obstacle_height: 2.0 raytrace_range: 3.0 footprint: [[-0.325, -0.325], [-0.325, 0.325], [0.325, 0.325], [0.46, 0.0], [0.325, -0.325]] #robot_radius: 0.46 footprint_padding: 0.01 inflation_radius: 0.55 cost_scaling_factor: 10.0 lethal_cost_threshold: 100 observation_sources: base_scan base_scan: {data_type: LaserScan, expected_update_rate: 0.4, observation_persistence: 0.0, marking: true, clearing: true, max_obstacle_height: 0.4, min_obstacle_height: 0.08}